Talk:Wave power/Archive 1

The formula shown for power seems suspect to me. I'm not an expert, but the referenced articles, if i am reading them right, say this is the power per wave. --agr 19:15, 24 March 2006 (UTC)

It must be power continuously, not per wave. One may speak of work per wave, not power per wave. Please don't change the formula casually.Anthony717 01:25, 27 March 2006 (UTC)

Anon
If we observe the wave, it is unidirectional. I am having a Idea to run a Rotor with blades(Turbine) over the Sea Surface. If any one have any Experience share the same. —Preceding unsigned comment added by 61.1.222.210 (talk • contribs)
 * What? -- Ec5618 13:19, 5 June 2006 (UTC)

The article states that the largest waves (not including storm-induced)reach 15 meters. Dont you mean feet?? 15 meters is a tsunami at work, and could crush a 3 story building. Does that need correcting??189.169.84.33 17:26, 25 September 2006 (UTC) Jenny

A fully developed sea with persistent 50 knot winds will have 15 meter waves.Anthony717 20:34, 3 November 2006 (UTC)

HOW about like the gorges dam

The effects of tapping this power?
The article is lacking a discussion of the effects of tapping the wave power. The energy has to come from somewhere; very probably, the effect of the floaters is to damp the waves. If they are incoming coastal waves, that will mean that vast tracts of shoreline will have less waves. Does that matter? There should be some discussion, or at least a mention of the problem. David Olivier 14:24, 21 February 2007 (UTC)


 * Wave energy is absorbed by the shore, whether or not wave power devices are present. Waves erode the shoreline and provide sport for surfers. Unless someone can point to some biological process that requires waves, this is non-issue.Anthony717 20:35, 23 February 2007 (UTC)


 * I would have thought this was a benefit, not a problem; surely a lot of what is spent on coastal defence would be saved in a wave power system. In fact coastal defence alone might justify the cost of a scheme, with the power as a by-product (I don't know the costs involved, I'm just speculating; I'd be interested if anyone has the answer to that). Moonraker12 14:51, 12 June 2007 (UTC)


 * There isn't a huge amount of research available into the effects of wave energy on the sea state after interaction with wave energy devices, largely due to the lack of practical experience with devices in situ. Some models have been applied but considerably more work is needed. There is some evidence of shoreline effects from models carried out in connection with the Wave Hub development in Cornwall, with estimations of a 1-3% reduction in wave height at the shore (based on 20MW of generator, 15km offshore). The impacts of this on shoreline marine life has not been investigated to my knowledge. It's not impossible that there could be some impact as there is evidence that even slight variations in sea state can lead to evolutionary differences amongst similar species with only slight geographical separations. biffa 11:13, 31 July 2007 (UTC)

Cost?
What would Wave Power cost to use and install at home? -Jallero 06:12, 27 February 2007 (UTC)
 * A lot. I read an estimate that one wave bearing costs $50,000 because of the salt water environment. 199.125.109.108 07:35, 9 July 2007 (UTC)
 * Then there is the cost of the canal... Moonraker12 14:00, 29 August 2007 (UTC)

Inappropriate template
The template:renewable energy sources has been vandalized to change it to say "Energy development" instead of "Renewable energy" which is what it should say. Nuclear power also needs to be deleted. Very few people think that nuclear power is "renewable energy". Template has been restored and protected for one week.199.125.109.108 07:35, 9 July 2007 (UTC)

Do we need to include wave power in project physics? 199.125.109.84 18:08, 15 July 2007 (UTC)

The costs of manufacturing wave buoy's
http://www.phenolics.org/products/PhenolicNL.htm

I was reading this article and have some knowledge of advanced materials and metallurgy and was impressed that the design could be constructed with Bakelite, MOST IMPORTANTLY the section in the article that says that initial designs will be over-engineered, corrode, etc;

There is a couple ways to make Bakelite but similar to boat hulls made with fiberglass a form is used, But I want to point out that Bakelite is HEATED and CURED where simple fiberglass is not!

Manufacturing could create large Bakelite Buoys that would be tensile strength strong enough and corrosion resistant.

Ohh, the phenoyl would be a by-product of ethanol produiction in B20 etc;

I would like more information on the pump design and some pictures of the power train of these systems.

If there was a real market today, I could bid Bakelite as a material and win the contract. —Preceding unsigned comment added by 70.21.116.163 (talk) 19:28, 25 September 2007 (UTC)

As I understand it most of the serious wavepower manufacturers plan to use concrete as the structural material with as much as possible of the other equipment enclosed and protected. But maybe bakelite has some applications. CostelloWaves 19:03, 5 November 2007 (UTC)

Discussion of Salter's Duck
Prior to my edit:
 * "According to sworn testimony before the House of Parliament, The UK Wave Energy program was shut down on March 19, 1982, in a closed meeting[1], the details of which remain secret. The members of the meeting were recruited largely from the nuclear and fossil fuels industries, and the wave programme manager, Clive Grove-Palmer, was excluded."

The source in question:
 * "I do not know if any peer review process was involved but I expect that everything was decided by ETSU and the Department of Energy, with long range control of a committee known as ACORD that was recruited largely from the nuclear and the depletable energy industries. It has not been possible to get minutes of their meeting of 19 March 1982 from which the wave programme manager, Clive Grove-Palmer, was excluded and at which it was decided to close the UK wave programme."

Here are the claims in the article text:
 * 1) "According ... Parliament," - Supported, but leads to a sinister assumption. Removed.
 * 2) "shut down on March 19, 1982," - Supported.
 * 3) "in a closed meeting[1], the details of which remain secret." - Not supported. The modifier "closed" assumes such meetings are usually "open". They are not. No assertion was made that the details were or are secret.
 * 4) "The members of the meeting were recruited largely from the nuclear and fossil fuels industries," Not supported. The source "do(es) not know" and says it was probably ETSU and the Dept. of Energy . . . with long range control of ACORD (which was recruited kind of from the sources indicated)
 * 5) "and the wave programme manager, Clive Grove-Palmer, was excluded." Supported.

Resulting text:
 * "The UK Wave Energy program was shut down on March 19, 1982, in a meeting from which wave programme manager, Clive Grove-Palmer, was excluded.[1]"

Mdbrownmsw 17:26, 28 September 2007 (UTC)

WikiProject class rating
This article was automatically assessed because at least one WikiProject had rated the article as start, and the rating on other projects was brought up to start class. BetacommandBot 10:05, 10 November 2007 (UTC)

This is starting to become a linkfarm
Unless anyone truly objects with a valid reason all those companies should be at the bottom of the page, I am going to do a bit of spring cleaning on this article. The external links are a mess in my opinion.  spryde |  talk  12:25, 19 December 2007 (UTC)


 * Strong Support - Looking at the scroll bar, the Article is 2/3rds links out. Let's start a new list of external links here, put in an excerpt for justification, and then transplant. As a newcomer, these are the sites I found useful, either through WP or googling:


 * Archimedes Wave Swing (AWS) http://www.awsocean.com/technology.html - Extracts energy from vertical motion from submerged gas-filled buoys. These buoys are actually pistons filled with gas that undergo a compression cycle based on the height of the water column that applies a downward force, F = mgh, where h and m, height and mass, respectively, fluctuate under gravitation (constant, g) as tides and waves pass over these fully submersed pistons.


 * Offshore Alternative Energy Generation http://www.aidis.org.br/span/ftp/OFFSHORE%20ALTERNATIVE%20ENERGY%20GENERATION.pdf - Includes topics, figures, tables, and equations: global distribution of wave power, McCabe pump, Pelamis "water snake", Archimedes Wave Swing (AWS), potential tidal energy power plant sites, map of major oceanic currents, turbine efficiency, and ocean thermal energy conversion.


 * Permanent Magnet Linear Generator Buoy - http://web.engr.oregonstate.edu/~prudell/index_files/WE_Brochure.pdf - Oregon State University has developed three direct-drive prototype buoys designed to be anchored 1-2 miles offshore, in typical water depths of greater than 100 feet, where the buoys will experience gradual, repetitive ocean swells.  Wave motion causes electrical coils to move through a magnetic field, inducing voltages and generating electricity.


 * US Patent 6,194,815 - A piezoelectric generator comprises one or more inner hubs, an outer, stationary support, and a plurality of strap-like piezoelectric power generating elements mounted between the hubs and the outer support. The hubs are mounted for relative rotation on a first shaft mounted eccentrically on a second shaft having an axis of rotation coincident with central axis of the outer support. Rotation of the eccentric first shaft causes the hubs to follow a circular path around the outer support axis but without rotation of the hub around its own axis. The movements of the hubs cause alternate straining and destraining of the piezoelectric elements for generating electrical energy. For obtaining high energy conversion efficiency, the elements are arranged in groups of three or more substantially identical elements which are identically strained but symmetrically out-of-phase with one another.


 * US Patent Application 20040217597 - An elongated cylinder is fully submerged, in vertical orientation, just below the mean water level of, e.g., and ocean, and of a length, dependent upon surface waves of preselected wavelength, such that the top of the cylinder experiences relatively large pressure variations in response to over passing waves while the bottom of the cylinder experiences an almost steady pressure substantially independent of the over passing waves. The pressure differential over the length of the cylinder is used for causing relative movements between the cylinder and adjoining water, and such relative movements are used for driving a piston of an energy converter. The cylinder can be hollow and in fixed location for causing water movements through the cylinder, or the cylinder can move through the water relative to a fixed transducer. In one version of the movable cylinder, the transducer is fixedly mounted on a fixed in place float disposed within the movable cylinder. In a second version, the transducer is fixedly mounted beneath the movable cylinder on the ocean floor, and the cylinder is coupled to the transducer.


 * Discovery Channel PowerBuoy - http://www.exn.ca/video/?video=exn20051114-buoy.asx - Video of the Ocean Power Technologies' PowerBuoy.


 * SeaHorse http://www.brooke-ocean.com/s_horse1.html - Utilizes low energy surfaces waves (15 cm height, 2 second period) to move a sensor platform up and down a mooring wire.

(We also need something easier to find than Tester et alia for Wave Power Equations, with a clear definition of whether KE, PE, both, experimental value, etc. is the criterion for what is being called energy.) —Preceding unsigned comment added by Nukeh (talk • contribs) 02:31, 25 March 2008 (UTC) 100TWdoug (talk) 02:34, 25 March 2008 (UTC)

the technology
The descriptions of the technology are deficient, IMO. A good description of a piece of technology ought to supply enough information to mentally picture the basic workings of the device. From the description of the buoy method, for example, I can envision three different ways the device could be generating power -- four, if I pair buoys. The information provided ought to discuss the options and make clear what is actually being done.Dismalscholar (talk) 03:26, 7 February 2008 (UTC)

More articles and devices needed
More devices need to be mentioned that exist to harness wave energy. A list on what devices to add can be found here. Add them to the article. Also, perhaps the Salter duck-article might be created (so the entire text does not need to stay on this article about the duck-question). Cheers guys,

KVDP (talk) 09:10, 20 February 2008 (UTC)

Wave powered boat - any details?
Hi, found something about a wave-powered boat http://www.tsuneishi.co.jp/english/horie/about.html Mentioned briefly on Wikipedia:Kenichi Horie. It doesn't give many details. Anybody knows something about it? —Preceding unsigned comment added by 128.139.226.36 (talk) 16:48, 29 February 2008 (UTC)

Restored sections
The following sections:

100 Terawatt GEWP Calculations

More 100 Terawatt GEWP Calculations

Potential

Animated Maps for Forecast Wave Height and Period

Request to Google Reneweables for Confirmation of 100 TW Calculation

Adoption or Joint Venture?

Have been deleted, apparently without discussion

There are also substantial changes within the sections, which make it difficult to follow the discussion. Does anyone know why?

Anyway I’ve restored what I can find.

Moonraker12 (talk) 10:16, 28 March 2008 (UTC)

100 Terawatt GEWP Calculations
Crowsnest has called the reference to this entry a "hoax" and has deleted it twice. If it is a hoax, then there would be a very clear item of misinformation, a bad calculation, or something Crowsnest should be able to point out that is clearly inconsistent with science and engineering. The single sentence characterizing the GEWP calculation and proposal has been deleted twice by Crowsnest without discussion. Where is Crowsnest evidence of a hoax? Why would another WP editor, namely myself, place a material that references a hoax in a WP article? That suggests vandalism. I am not a vandal. The real vandal is anyone or any entity that would seek to supress the GEWP calculation. Candidates include the USA Department of Energy and people who are directly affected by the calculation in terms of their financial livelihood or their stated public position.Nukeh (talk) 10:39, 8 March 2008 (UTC)


 * Yes, I‘m having trouble with this


 * The article says 5,000 km of coastline is required to yield 50 GW (50,000 MW), though, to be fair, that claim isn't referenced; This claims that GEWP refers to a scheme to produce 100 TW (100 million MW)!.


 * It does this by using 100,000 floats the size of the Exxon Valdez ( that’s a total of 20,000 million tons of floating steel)


 * Also, the GEWP website is only a week old, and refers back to here.


 * What does anyone else think?


 * Moonraker12 (talk) 14:11, 8 March 2008 (UTC)


 * Regarding calling the GEWP energy device claims a hoax: my apolagies, if it is not.
 * Regarding your contributions to this article and talk page, and elsewhere on Wikipedia: Wikipedia is not the place to present original research, nor is this talk page a forum for (at length) discussing original research, see WP:NOT. So I suggest Nukeh to search outside Wikipedia for presenting his research and claims, as well as for asking validation of these claims and for obtaining advice on water wave dynamics, ship hydrodynamics and wave energy. Which I expect not to be difficult, regarding Nukeh's professional background and contacts.
 * Crowsnest (talk) 12:30, 9 March 2008 (UTC)

More 100 Terawatt GEWP Calculations
Global Wattage / Wolf Creek Wattage = 100 million MW / 1,000 MW = 1014 / 109 = 100,000 nuclear reactors (although Wolf Creek is a high record holder). If the GEWP calculations are correct, would it be better to have one Valdez-sized ocean-based generator riding on waves, or one new land-based nuclear reactor? Nukeh (talk) 20:39, 8 March 2008 (UTC)

Here is one of the calculations from GEWP.org:

Estimate of total world energy use: 1014 W = 100 terawatts

5 x 1015 ft·lbf/min

5 x 1014 ft·gal/min

(Assume unidirectional wave motion of 15 ft / min and a mechanical-to-electrical conversion efficiency of 30%)

1014 gal of displacement in such motion

1013 cubic feet

1012 square feet of a 10 foot thick slab

106 ft x 106 ft x 10 ft displaced slab

200 mile x 200 mile x 10 foot slab

What part of this calculation constitutes a "hoax"? Nukeh (talk) 13:46, 8 March 2008 (UTC)


 * Yeah... That's the size of Iceland; maybe that's where the "hoax" idea comes from, Hmm? Moonraker12 (talk) 14:15, 8 March 2008 (UTC)

It's also half the size of Kansas. But, for the moment, let's assume size doesn't matter. I'd still like to know if the physics is correct. Once that is confirmed, then it is highly appropriate to challenge the materials science, engineering scale, cost, environmental impact, geopolitical compensatory benefits (avoiding buzz words, here), other remedies for greenhouse, etc.Nukeh (talk) 15:42, 8 March 2008 (UTC)

Potential
I've moved this:-

"A 100 terawatt plan — exceeding total human energy use — has been proposed using buoyant vessels tethered to the ocean floor with a distributed displacement volume of 200 miles (320 km) by 200 miles x 10 feet (3.0 m)."

as it 's disputed (see discussion above). Please do not replace it until there is consensus on it. Moonraker12 (talk) 14:20, 8 March 2008 (UTC)


 * We should also question the 100TW number in reference to http://www.eia.doe.gov/oiaf/ieo/graphic_data_world.html -see their Figure 8, in spreadsheet form, from their Figure 8. "World Marketed Energy Consumption, 1980-2030 Quadrillion Btu"

Here are my notes on the conversion to Watts, which I continue to revise between these formatting lines (if that is OK under WP rules):

Year	Quadrillion BTU

1980	283.4

1985	308.6

1990	347.3

1995	365.6

2000	399.6

2004	446.7

2010	511.1

2015	559.4

2020	607.0

2025	653.6

2030	701.6

1 Watt is approximately 3.41 BTU/hr

Quadrillion may mean either of the two numbers (see long and short scales for more detail):

1,000,000,000,000,000 (one thousand million million; 1015; SI prefix peta) - increasingly common meaning in English language usage.

1,000,000,000,000,000,000,000,000,000,000,000,000,000,000 (1024; SI prefix yotta) - increasingly rare meaning in English language usage.

Year 2010: 511.1 x 1015 BTU

divide by 3.41 (1 watt is approximately 3.41 BTU/h) and divide by 8760 (hours per year) to get

5 x 1012 Watts

Perhaps DOE data is in BTU / day, then yielding 120 TW: 511.1 x 1015 BTU, divide by 3.41, divide by 365; DO NOT divide by 24.

Nukeh (talk) 17:58, 8 March 2008 (UTC)

Is it appropriate for one of the other WP to contact roger.c.prince@exxonmobil.com (and colleagues) via email to verify these energy units and conversion factors, and then post here? Please note that I / we simply want to make WP entires consistent in terms of world energy quotes and conversion factors that are already referenced on WP. As I understand the WP rules 'original research' is a no no. However, quotes and conversion factors, especially if cited in the wrong units, are editorial jobs that can be performed at a textbook level using internal WP references. It would be a HUGE JOB for a WP editor to go through the entire website and look for errors in the plethora of citations on energy and power units! Once bad numbers get out, they are hard to recall, because WP is often viewed as authoritative by students and readers.Nukeh (talk) 18:30, 8 March 2008 (UTC)

Director Chu at Lawrence Berkeley Laboratory is also aware of this calculation 'SChu@lbl.gov'. Perhaps another editor can get him to confirm the calculation or to refer us to the appropriate DOE publication. Also, there is work at OSU funded by DOE that is already referenced on WP.Nukeh (talk) 20:27, 8 March 2008 (UTC)

Another person that might be able to confirm the calculation is the current chair of UN-Energy, Mats Karlsson, of the World Bank. Nukeh (talk) 03:06, 12 March 2008 (UTC)

Animated Maps for Forecast of Wave Height and Period
- 0 to 168 hour forecast in 6 hour intervals, with a color-coded scale from 0 to 75 feet. Just South of New Zealand looks like a wild place!

is a possibility for the main article. It has a nice user interface with 22 buttons for views x 2 options for either wave period or wave height, and a drop down menu for forecast time, including an animated gif. This entry reformatted and resigned by Nukeh (talk) 21:29, 11 March 2008 (UTC)Nukeh (talk) 00:21, 12 March 2008 (UTC)

Request to Google Renewables for confirmation of 100 TW Calculation
renewables@google.com 100 terawatt calculation

Google,

Please see www.gewp.organd http://en.wikipedia.org/wiki/Talk:Wave_power.

The calculation on ocean waves (naturally wind-powered) has been up 10 days.

The total platform now looks more like 100 x 100 miles x 10ft displacement for 100 terawatts, equal to current world power.

Using freshman-college-level physics, and the references on GEWP, someone in your organization should be able to confirm the calculation with about one hour of work. I would ask you to place the confirmation statement on the WP Talk: Wave Power page, using a well-established user name. Otherwise, WP will think the confirmation is coming from a sock puppet.

No one at DOE, Exxon, academia, etc. has touched that talk page in a substantial manner since my calculation went up on March 1, 2008, despite repeated requests from me to old colleagues via email and a lot of targeted “advertising” using Google AdWords.

I conclude that the calculation is probably correct, but that the topic is hotter than Cold Fusion.

Respectfully,

Doug Youvan 1-808-783-0180 Nukeh (talk) 04:07, 12 March 2008 (UTC)

Adoption or Joint Adventure?
After 2 weeks on Wave Power, it is fairly clear that page is very important to Alternative Energy and it needs to be re-written to bring it up to speed and exceed the Discovery Channel. No joke, I just added 2 patents to the main article, tracked the assignee, and saw their work on a Discovery clip. Fabulous stuff. Given that I am conflicted with www.gewp.org, what can we (mouse in my pocket) / I do to help re-write the article and push it up in importance in the appropriate portals? Not only am I conflicted with gewp, but I am running Google Adwords on the keywords "alternative energy" and "wave power", world-wide. That's half my income, so you might be able to see that I am very serious about doing anything I can to head off (buzz words deleted) over energy.Nukeh (talk) 20:28, 13 March 2008 (UTC)
 * Did you just say that you have a financial interest in seeing this article's position in search engine's improved, and that is your motivation for editing it in a certain way? I just want to be clear on that.  Please clarify --Jayron32. talk . contribs  20:31, 13 March 2008 (UTC)

I am financially conflicted in the opposite manner as normally encountered: My work for gewp.org is pro bono and gewp.org itself places all new technology into the public domain, creating a patent bar immediately upon publication. My payment for AdWords is a charitable contribution to gewp, and gewp is a 501(c)3 nonprofit in formation. I do this as an experienced inventor in biotechnology, having ~600 uspto.gov patent references. One of my patents was litigated through three levels of court up to the CA Supreme Court in 2006, and the award was a record: $34.5M. I also figure the US government has ~ $50M in me via grants and training over a 30 year period. Given the status of energy in our world, and some of the obvious consequences for the future (war, stagflation, greenhouse, nuclear proliferation, etc.), I feel that I have no choice but to act in a charitable manner as an inventor. My affiliations are exclusively to www.gewp.org, and other charitable organizations, having retired from all other work years ago. I have no financial interest in anything except blinded CA State bonds which are the current source of my charitable giving.Nukeh (talk) 02:13, 14 March 2008 (UTC)


 * Still, you have, as you say, a vested interest in pushing certain things up in importance in appropriate portals; which to me means that your editing is based on search engine hits and NOT on producing the best encyclopedia. That is a conflict of interest of the WORST kind, regardless of whatever financial stake you have in the matter.  The fact remains that you aren't interested in creating balanced, neutral, or accurate articles, only in playing the Google game.  That is directly counter to Wikipedia's core mission.  You should seriously reconsider your motivation here at Wikipedia... Your actions will likely get you into trouble.  --Jayron32. talk . contribs  03:48, 14 March 2008 (UTC)

If the wave power article is not as current as a Discovery program, and someone has blanketed the article with wave gizmos that consist of 404's and "contact the company for more information", why would you question my philanthropic motives? Every day, I am bidding directly against Chevron and others to increase traffic on keywords such as "alternative energy".

We are all in trouble: The fact of the matter is that it is now feasible to convert either to solar or wave power for a Hydrogen economy. The references are on www.gewp.org. These references need to be on WP, because WP is seen as more authoritative than gewp.

Here is another problem: It appears that there is no legitimate purpose for new nuclear plants if solar and/or wave is adequate. If that becomes both USA domestic and foreign policy, then we are in a strong position to deter nuclear proliferation via reactors constructed on the premise of energy supply. However, to say that solar and / or wave power is adequately sufficient to power all of mankind at 100 terawatts is also to say that the oil industry is condemned.

Please direct me to the appropriate WP rules for a sole inventor, sole source, philanthropist who wishes to contribute to articles. Nukeh (talk) 05:14, 14 March 2008 (UTC)


 * You are argueing like I care about the specifics of the situation. As a Wikipedia administrator, I am officially neutral on those issues, and take the official position of not caring at ALL about this information.  However, you REALLY should read WP:COI and take it to heart, because it clearly looks like you have a conflict of interest in the articles in question...--Jayron32. talk . contribs  05:21, 14 March 2008 (UTC)

Thank you. WP:COI is a specific instruction that I will read and follow. Nukeh (talk) 05:25, 14 March 2008 (UTC) I should add that I am potentially conflicted by, too. Nukeh (talk) 05:33, 14 March 2008 (UTC)

I have read conflict of interest:
 * Some editors declare an interest in a particular topic area. They do this in various ways. Many Wikipedians show their allegiances and affiliations on their user pages. You may choose to reveal something about yourself in a talk page discussion. Disclaimer: Wikipedia gives no advice about whether or how to use its pages to post personal details. This guideline only raises some pros and cons.


 * Advantages:


 * By declaring an interest, you pre-empt anyone outing you or questioning your good faith.
 * Most editors will appreciate your honesty.
 * You lay the basis for requesting help from others to post material for you, or to review material you wish to post yourself.

So, I believe I am in compliance, and no one seems to understand: "requesting help from others to post material for you". Nukeh (talk) 05:42, 14 March 2008 (UTC)


 * Yeah, but I'm not really interested in posting the material for you. Try the talk page of the relevent articles.  Someone there may be able to vett the information you wish to add, and be willing to help out.  I'm just not that interested myself... --Jayron32. talk . contribs  05:49, 14 March 2008 (UTC)

OK, moved to article discussion Nukeh (talk) 10:42, 14 March 2008 (UTC)

This is a copy-paste from my Adwords ~ 1 week timescale:

Keyword Status   Current Bid Max CPC Show Settings Hide Settings Sort by: Bid | URL Clicks  Impr. CTR Avg. CPC Cost  Avg. Pos Alternative Energy Active $1.11 Settings

$1.11 Max CPC http://www.gewp.org [ Edit ] 280 18,612  1.50%  $0.94  $262.85  4.4 Wave Power Active $0.40 Settings

$0.40 Max CPC http://www.gewp.org [ Edit ] 4 460  0.86%  $0.37  $1.46  2.0 Department of Energy Deleted     3  1,761  0.17%  $0.50  $1.50  1.3 Tidal Energy Deleted     16  1,175  1.36%  $0.19  $2.99  2.3 Wave Energy Deleted     20  984  2.03%  $0.18  $3.54  2.4 wave power Deleted     0  122  0.00%  -  -  1.3 tidal power Deleted     0  121  0.00%  -  -  1.4 "wave power" Deleted     0  24  0.00%  -  -  1.5 Clinton Energy policy Deleted     1  6  16.66%  $0.50  $0.50  2.0 McCain Energy policy Deleted     0  4  0.00%  -  -  2.3 Obama Energy policy Deleted     0  2  0.00%  -  -  2.0 Obama energy Deleted     0  2  0.00%  -  -  3.0 Hilary Clinton energy Deleted     0  1  0.00%  -  -  2.0 Hilary Clinton energy policy Deleted     0  1  0.00%  -  -  2.0 alternative energy policy Deleted     0  1  0.00%  -  -  6.0 Content network total  Off        266 149,983 0.17%  $0.55 $145.80 3.5 Search total On Default  $0.40 [Edit]   324 23,276 1.39%  $0.84 $272.84 3.9 All sources total      590 173,259 0.34%  $0.71 $418.64 3.6

Nukeh (talk) 10:59, 14 March 2008 (UTC)

If anyone finds this interesting: The gewp.org $1.11 bid per click is currently outbid by two Chevron ads, GE, and a book ad for Earth the Sequel. Nukeh (talk) 14:40, 14 March 2008 (UTC)

-

Archiving?
If these discussions (above) are complete, we could archive them; does anyone know where things are up to? Moonraker12 (talk) 10:19, 28 March 2008 (UTC)
 * I think that everything can be archived. Relevant to leave here or copy back: . Crowsnest (talk) 10:27, 28 March 2008 (UTC)

Talk Page Archive
Archive 1 has been created with a link at above right. It is an exact copy of the talk page as it was before this edit. Archive 2, when needed in the future, should be a new subpage (same as creating an article) titled "Talk:Wave power/Archive 2" and the link added to the template on this page's code. For further information on archiving see How to archive a talk page. See also User:5Q5 for the used archiving procedure. Thank you. Crowsnest (talk) 12:58, 28 March 2008 (UTC)

This is starting to become a linkfarm
Unless anyone truly objects with a valid reason all those companies should be at the bottom of the page, I am going to do a bit of spring cleaning on this article. The external links are a mess in my opinion.  spryde |  talk  12:25, 19 December 2007 (UTC)


 * Strong Support - Looking at the scroll bar, the Article is 2/3rds links out. Let's start a new list of external links here, put in an excerpt for justification, and then transplant. As a newcomer, these are the sites I found useful, either through WP or googling:


 * Archimedes Wave Swing (AWS) http://www.awsocean.com/technology.html - Extracts energy from vertical motion from submerged gas-filled buoys. These buoys are actually pistons filled with gas that undergo a compression cycle based on the height of the water column that applies a downward force, F = mgh, where h and m, height and mass, respectively, fluctuate under gravitation (constant, g) as tides and waves pass over these fully submersed pistons.


 * Offshore Alternative Energy Generation http://www.aidis.org.br/span/ftp/OFFSHORE%20ALTERNATIVE%20ENERGY%20GENERATION.pdf - Includes topics, figures, tables, and equations: global distribution of wave power, McCabe pump, Pelamis "water snake", Archimedes Wave Swing (AWS), potential tidal energy power plant sites, map of major oceanic currents, turbine efficiency, and ocean thermal energy conversion.


 * Permanent Magnet Linear Generator Buoy - http://web.engr.oregonstate.edu/~prudell/index_files/WE_Brochure.pdf - Oregon State University has developed three direct-drive prototype buoys designed to be anchored 1-2 miles offshore, in typical water depths of greater than 100 feet, where the buoys will experience gradual, repetitive ocean swells.  Wave motion causes electrical coils to move through a magnetic field, inducing voltages and generating electricity.


 * US Patent 6,194,815 - A piezoelectric generator comprises one or more inner hubs, an outer, stationary support, and a plurality of strap-like piezoelectric power generating elements mounted between the hubs and the outer support. The hubs are mounted for relative rotation on a first shaft mounted eccentrically on a second shaft having an axis of rotation coincident with central axis of the outer support. Rotation of the eccentric first shaft causes the hubs to follow a circular path around the outer support axis but without rotation of the hub around its own axis. The movements of the hubs cause alternate straining and destraining of the piezoelectric elements for generating electrical energy. For obtaining high energy conversion efficiency, the elements are arranged in groups of three or more substantially identical elements which are identically strained but symmetrically out-of-phase with one another.


 * US Patent Application 20040217597 - An elongated cylinder is fully submerged, in vertical orientation, just below the mean water level of, e.g., and ocean, and of a length, dependent upon surface waves of preselected wavelength, such that the top of the cylinder experiences relatively large pressure variations in response to over passing waves while the bottom of the cylinder experiences an almost steady pressure substantially independent of the over passing waves. The pressure differential over the length of the cylinder is used for causing relative movements between the cylinder and adjoining water, and such relative movements are used for driving a piston of an energy converter. The cylinder can be hollow and in fixed location for causing water movements through the cylinder, or the cylinder can move through the water relative to a fixed transducer. In one version of the movable cylinder, the transducer is fixedly mounted on a fixed in place float disposed within the movable cylinder. In a second version, the transducer is fixedly mounted beneath the movable cylinder on the ocean floor, and the cylinder is coupled to the transducer.


 * Discovery Channel PowerBuoy - http://www.exn.ca/video/?video=exn20051114-buoy.asx - Video of the Ocean Power Technologies' PowerBuoy.


 * SeaHorse http://www.brooke-ocean.com/s_horse1.html - Utilizes low energy surfaces waves (15 cm height, 2 second period) to move a sensor platform up and down a mooring wire.

(We also need something easier to find than Tester et alia for Wave Power Equations, with a clear definition of whether KE, PE, both, experimental value, etc. is the criterion for what is being called energy.) —Preceding unsigned comment added by Nukeh (talk • contribs) 02:31, 25 March 2008 (UTC) 100TWdoug (talk) 02:34, 25 March 2008 (UTC) User:Crowsnest has fixed. 100TWdoug (talk) 15:41, 28 March 2008 (UTC)

Recent deletions in Company and institutional links (with technology descriptions): Deleted all 404's and advertisements. Please don't undo the 404's. If I hit something useful, please aim hyperlink at a page with more information on it, one by one. This should also serve to remove dead companies. 50MWdoug (talk) 00:02, 29 March 2008 (UTC)

Recent deletions in Sources and external articles:Deleted all 404's. Please don't undo the 404's.  If I hit something useful, redo one-by-one, else the link farm will resprout.50MWdoug (talk) 01:38, 29 March 2008 (UTC)

the technology
The descriptions of the technology are deficient, IMO. A good description of a piece of technology ought to supply enough information to mentally picture the basic workings of the device. From the description of the buoy method, for example, I can envision three different ways the device could be generating power -- four, if I pair buoys. The information provided ought to discuss the options and make clear what is actually being done.Dismalscholar (talk) 03:26, 7 February 2008 (UTC)

Archiving?
If these discussions (above) are complete, we could archive them; does anyone know where things are up to? Moonraker12 (talk) 10:19, 28 March 2008 (UTC)
 * I think that everything can be archived. Relevant to leave here or copy back: . Crowsnest (talk) 10:27, 28 March 2008 (UTC)
 * I archived to /Archive 1 on March 28, see top of this page. Crowsnest (talk) 00:52, 29 March 2008 (UTC)

Edit & Improve, Don't Remove Good Content
P=(1,025kg/m3)((9.8m/s2)^2)((32pi)^-1)TH2; where T is time in seconds, H is height in meters (this is height above sea level or amplitude) and P is watts per meter (of coastline). So, (1025*(9.8^2))/(32*pi)=979.210735, in watts, which is about 1 kilowattt. Therefore, use crest-to-crest wave height, which is easier for the average person the visualize (since it's the apparent height to a swimmer), and we get "Power (in kW/m) = k H² T ~ 0.5 H² T". It's fine to add more math, but don't take away the simple equation that most people could understand.
 * "Power (in kW/m) = k H² T ~ 0.5 H² T" is correct. See "Technology White Paper on Wave Energy Potential on the U.S. Outer Continental Shelf" & other government produced papers. To wit:
 * The "technology descriptions" subsection is a fun & informative part of Wikipedia that I put a lot of effort into. The subsection was ruthlessly pruned. It is more than a list and more than links: therefore it passes the test of such standards as are discussed in The Economist's recent article "The battle for Wikipedia's soul". In the battle between “inclusionists” and “deletionists”, deletionists must be held to a higher standard -- because their indulgences deprive the reader of knowledge; whereas a little extra (correct) information hurts nobody.Anthony717 (talk) 20:57, 8 April 2008 (UTC)
 * There are however, regarding the restored section on wave power, quite some comments regarding the "good content", which is why it was replaced and improved upon in the first place:
 * The simple power equation as given, is original research, in contradiction with WP:NOR. None of the mentioned references, including the White Paper referenced above, gives this formula. It is also in error, since the constant computed by you is in error, see below. Neither are limitations of this formula stated, e.g. deep water waves.
 * The first reference, http://www.engin.umich.edu/dept/name/research/projects/wave_device/wave_device.html, is erroneous in its interpretation and calculation of wave power, multiplying the wave energy with wavelength and dividing by wave period. This is effectively saying that wave power is energy density times phase velocity, instead of energy density times group velocity (which is known since the 19th century: e.g. Stokes, Rayleigh, etc.). This results in an overestimation of wave power by a factor of two. Then this reference goes on with calculating "power density" per unit horizontal area, suggesting a totally erroneous view of wave power, lacking the insight that wave power or wave energy flux is the horizontal transport rate of wave energy.
 * The other reference, http://www.esru.strath.ac.uk/EandE/Web_sites/01-02/RE_info/wave%20power.htm, the above mentioned White Paper, and the text (including references therein) as it was before your edits of April 8, 2008, just contain effectively the same formula's for the deep-water case, not containing your misinterpretations and errors in calculating the wave power "constant".
 * Using these formula's, you correctly calculate (apart from the units) above that the wave energy flux (wave power) for T=1 second and H=1 meter is about P≈1000 watt per meter width perpendicular to the wave direction. Then you assume the White Paper is talking not about wave height (while it clearly states is does), but wave amplitude. Thereafter you make another error, since the power is proportional to wave height squared, so if it would have been wave amplitude (but it is not) it should have been divided by 2 squared (equals 4), instead of by 2 as you did. This makes also the wave power estimate for the 15 second, 15 meter high wave erroneous in the text restored by you. You did not make the effort to look into the same section below the new formulas, where the same example is calculated giving a different answer.
 * It says: "The potential energy of a set of waves is proportional to wave height squared times wave period", which is pure nonsense. Potential energy density, integrated over depth, is per unit horizontal area, and proportional to the wave height squared. And the potential energy of a certain area that has to be multiplied by that area. Something proportional to wave height squared times period has certainly nothing to do with potential energy.
 * Also the sentence "wave energy is also present as pressure waves in deeper water" has been restored by you. In progressive waves, as commonly found at sea, the pressure fluctuations reduces exponentially with depth, in the same way as the velocities, see e.g. Phillips (1977), Goda (2000) or any other good book on water waves. Only in standing waves there are pressure oscillations not attenuating with depth, creating microseisms, but too small to be interesting from the point of view of wave energy devices.
 * I removed the offending part from the "Physical concepts" section, and added a simple formula for the wave power in the deep water case (which is not OR, since I just take the formula from the White Paper, and use standard gravity and mass density of sea water to compute it).
 * I did not look at the other sections where you restored "good content", and leave that to others. Crowsnest (talk) 00:48, 9 April 2008 (UTC)


 * I'm sorry that my formula was wrong. I could have sworn I got the k=0.5 from a good source in the past. Anthony717 (talk) 02:19, 9 April 2008 (UTC)
 * I'm not sure how to show that T in the wave power formula is the 'zero-crossing period' in the general, irregular wave case. It is not spelt out there. It would be great if someone could help with this, possibly citing some reference. Bodait (talk) 10:00, 7 October 2009 (UTC)

Factor two in wave energy and power

 * Hello I'm new to this wikipedia thing, but I did see an error in the maths/physics at this page. The total energy for a regular wave is indeed 1/8 \rho g H^2 (standard linear theory), but it changes for a real-life irregular wave field. If you fill in the definition of the statistical parameter H_{m0} = 4 sqrt{m_0}, where m_0 is the variance of the surface elevation, which is 1/2 a^2 = 1/8 H^2, for a regular (sine) wave (a is amplitude = H/2, but H - as normal in wave theory - is total wave height, crest to trough), the definition becomes E = 1/16 \rho g H_{m0}^2. This gives an estimate of 0.5 H_{m0}^2 T kW, and 64 in the denominator of the first equation, instead of 32. (Bas Hofland). —Preceding unsigned comment added by 145.9.225.170 (talk) 08:54, 10 June 2008 (UTC)
 * Thanks for pointing this out. This has been corrected. -- Crowsnest (talk) 12:06, 10 June 2008 (UTC)
 * To avoid confusion for editors, it would be great to have a source explicitly stating the values for this formula. Even with the correct information posted here, editors have, understandably (none of the listed sources have this formula given with the stated conditions and associated values), changed the main page values. --E8 (talk) 01:23, 19 February 2011 (UTC)
 * Done - thanks Crowsnest.--E8 (talk) 20:53, 19 February 2011 (UTC)

New source article in The Economist
New article in The Economist, "The coming wave," in the 7 Jun 2008 edition (pp. 22 of Technology Quarterly in the US print edition). Would be useful to mine for additional info for the WP article. Online reference is. N2e (talk) 21:24, 11 June 2008 (UTC)

Wave_power
This section is really out of control. Links do not belong in the body of the article. I propose to bring the section in line with the Manual of Style by removing the links or non-notable items. E_dog95'  Hi ' 23:20, 3 October 2008 (UTC)


 * To my opinion, the page has been improved a lot! I am glad all these links have gone. What is missing is some technology descriptions (for which the company links are not an alternative). -- Crowsnest (talk) 21:01, 23 October 2008 (UTC)

Potential
In this edit by S.Portland, the estimate of wave-power potential: "Deep water wave power resources are truly enormous, between 1 TW and 10 TW, but perhaps impractical to capture." with as its reference: was removed, including the reference. The above reference itself refers - with regards to this estimate - to the peer-reviewed article:
 * , 204 pp. See page 7.

It was replaced with: "It is estimated that world-wide the economically recoverable power from waves is 2 Terawatt annual average.", with reference:

presented at an IMechE seminar in 1999, of which I do not know whether (published) contributions were reviewed. In this new reference I have not been able to find the given estimate of 2 TW annual average yet. So I have doubts about the reliability of the new estimate. -- Crowsnest (talk) 19:00, 13 October 2008 (UTC)


 * I found the 2 TW estimate in Thorpe (1999), in the lead section: "The useful world-wide resource has been estimated at > 2 TW (WEC, 1993)", with:
 * So it is estimated to be larger than 2TW, instead of "is 2 TW", in this ref. -- Crowsnest (talk) 09:56, 24 October 2008 (UTC)
 * So it is estimated to be larger than 2TW, instead of "is 2 TW", in this ref. -- Crowsnest (talk) 09:56, 24 October 2008 (UTC)

Move of Salter's Duck material to Stephen Salter
The move of the material on Salter's Duck from here to Stephen Salter has the side effect that this important episode in the history of wave power is now almost completely gone from the article (apart from the 2 patents and one news item). It will only be found if going to the Stephen Salter article, instead of the Stephen Salter article referring to here. While Salter duck (as also used in the "Stephen Salter" article) redirects to here, with nothing on the subject. Any ideas how to solve this? -- Crowsnest (talk) 02:07, 2 March 2009 (UTC)
 * I apologize for any problems I've caused. Feel free to revert, whole or in part.  Basically, Stephen Salter was a very small stub, and I was trying to expand it by centralizing information.  I agree that it should be mentioned here, however, this article could use a bit more organization, particularly in terms of the types of wave power devices and its place in the historical timeline. Viriditas (talk) 12:16, 2 March 2009 (UTC)
 * I would like to see whether someone has a better solution than a simple revert of the move. The information is both relevant for here and it is important in the biography of Stephen Salter. A pure copy of the material on both pages seems silly, regarding the link possibilities of WP. I will try to find another solution. Suggestions are welcome. -- Crowsnest (talk) 12:25, 2 March 2009 (UTC)
 * One solution would be to create an article just for Salter's Ducks, and use summary style sections (Main article: Salter's Ducks) in this and the Stephen Salter article. That way each article could pick and choose whether to discuss specific information. Viriditas (talk) 12:43, 2 March 2009 (UTC)
 * What we have on Salter's Duck, at the moment, is a bit thin for a separate article. Anyway, as a "provisional" solution I copied the material back in. Still looking for a better way to solve this. -- Crowsnest (talk) 15:04, 2 March 2009 (UTC)
 * I would like to suggest we move the material on Salters Duck to its own page (it can be expanded over time) and replace it with a 'History' section as is the case in the Wind Power page. This allows discussion of other important early devices whist ensuring Salters Duck does not go unmentioned.  I am happy to make these changes if agreeable. S.Portland (talk) 15:10, 14 August 2009 (UTC)

Water Power formula
The section states that "In major storms, the largest waves offshore are about 15 meters high and have a period of about 15 seconds." I don't know about the period, but should that not read something rather like "regular waves"? Since freak waves can reach more than twice that height, approximately. Regards, --G-41614 (talk) 09:12, 9 June 2010 (UTC)

Wave equations
The following comment was entered by User:129.206.32.243 into the article itself...

The formulas and results above appear to be wrong. According to the book "The Future of Our Energy Provisions" (Pelte, D. (2010). Die Zukunft unserer Energieversorgung. Vieweg Teubner. ISBN 978 3 8348 0989 6) the wave intensity I (= power P per area A) is given by


 * $$\frac{P}{A} = \frac{\rho g}{6} \frac{H^2}{T}$$

This corresponds to the very general relation between intensity and energy density w (= energy W per volume V)


 * $$I = w v$$

where v is the velocity of the energy carrier. In the case of ocean waves one has


 * $$w = \rho g H$$ and   $$v = \frac{H}{T}$$.

The factor 1/6 is due to the fact that the water does not move with constant velocity on a straight trajectory (like the wind does in the case of wind power) but on circular orbits. Therefore the two examples given above should yield

P/A = 1.88 kW/sqm (instead of 36 kW/m)

P/A = 25 kW/sqm (instead of 1.7 MW/m)

If the power per m coast line is requested these numbers should be multiplied by H.

A few more inconsistencies which I added after my corrections were removed:


 * Since $$P \propto T$$ in this article it follows that $$P \rightarrow \infty$$ when $$T \rightarrow \infty$$ which is the condition for no waves (remember that $$c = \frac{\lambda}{T}$$ in linear wave theory). This result is unreasonable, the correct result should be $$P \rightarrow 0$$ for $$T \rightarrow \infty$$.


 * In this article the quantity E has the unit [E] = kg/s^2, as it should be. But then the quantity $$P = E c$$ has the unit [P] = kg m/s^3 whereas the correct unit for P should be kg/s^3.


 * To be consistent with the Physics definitions of power P and energy E the equation $$P = E c$$ ought to be replaced by $$P = \frac{E}{T}$$. Then the power formula is retrieved which I have used in my calculations, except that the factor f = 1/6 has changed to f = 1/16. This new factor lowers the calculated numbers even further and probably represents the more realistic situation of variable wave heights, i.e. the power formula for ocean waves depends on how H is defined. But in any case and regardless of the definition, its general form is explicitely determined as


 * $$\frac{P}{A} = f \rho g \frac{H^2}{T}$$.

D. Pelte129.206.32.243 (talk) 07:22, 9 August 2010 (UTC)

—Preceding unsigned comment added by 129.206.32.243 (talk) 14:32, 6 August 2010 (UTC)

--Epipelagic (talk) 11:04, 5 August 2010 (UTC)

Moved from main page
The following was placed on the main page, but was likely intended for this page: Jefferdogw (talk) 18:06, 28 September 2010 (UTC)*A very simple method of bringing the power ashore is illustrated at www.waveenergyco.com It involves a teeter-totter anchored to the ocean bottom, with one end tilted up so that a steel cable can be attached and come to shore where generation can occur in a maintenance-friendly environment. The other end is attached to a simple float/point absorber. --E8 (talk) 19:13, 28 September 2010 (UTC)

Coracle
I was wondering that the Coracle might also be used to construct a device for wave energy harvesting. Not sure how though. 91.182.251.170 (talk) 14:59, 20 November 2010 (UTC)
 * Would probably work better than several of the devices mentioned in the article now, but without reliable sources it cannot be included. -- Crowsnest (talk) 15:25, 20 November 2010 (UTC)

WaveRoller
IMO there are enough sources for WaveRoller. See http://www.google.com/search?hl=fi&rls=com.microsoft%3A*&q=waveroller&btnG=Haku&aq=f&aqi=&aql=&oq=&gs_rfai= --Teveten (talk) 10:47, 9 December 2010 (UTC)
 * Yes, you are right. When leaving out the company name, I do find news coverage on the WaveRoller. I will restore the entry and add the Scientific American article as reference. -- Crowsnest (talk) 11:01, 9 December 2010 (UTC)
 * OK, br --Teveten (talk) 11:03, 9 December 2010 (UTC)

Editors, please understand the difference between power and energy
Almost every article in the media gives meaningless statistics on electricity generation when they confuse the energy (which is how you price electricity) and power (the rate at which you produce energy). The units of power are Watts, W, kW, MW, GW etc. A wave power plant usually cites a constant amount of power as its output, eg. a 100 MegaWatt generator can service 50,000 homes. The price that they set is for the amount of energy they sell (energy = power multiplied by time in kiloWatt-hours or kWh). Your utility might charge 10 cents per kilowatt hour. It is meaningless to charge per kilowatt, just as it is meaningless for a utility to produce 100 kWh. — Preceding unsigned comment added by Pioneeranomoly (talk • contribs) 14:23, 5 February 2011 (UTC)

External links modified
Hello fellow Wikipedians,

I have just added archive links to 1 one external link on Wave power. Please take a moment to review my edit. If necessary, add after the link to keep me from modifying it. Alternatively, you can add to keep me off the page altogether. I made the following changes:
 * Added archive http://web.archive.org/web/20110711002325/http://www.finavera.com/files/2010-07-02%20Finavera%20Renewables%20announces%20sale%20of%20Ocean%20Energy%20division.pdf to http://www.finavera.com/files/2010-07-02%20Finavera%20Renewables%20announces%20sale%20of%20Ocean%20Energy%20division.pdf

When you have finished reviewing my changes, please set the checked parameter below to true or failed to let others know (documentation at ).

Cheers.—cyberbot II  Talk to my owner :Online 16:12, 28 February 2016 (UTC)

European OWC Wave Power Plant on the Island of Pico/Azores
Installed in PICO island in 1998-1999, stoped working for a few years then picked-up production around 2010 up until now. Just visited it last week (7MAY2016). Still running. power plant web site: http://www.pico-owc.net/ utility statistical information regarding production to the grid: http://www.eda.pt/Mediateca/Publicacoes/Producao/Paginas/Produ%C3%A7%C3%A3o-de-Energia-El%C3%A9trica.aspx Azores goverment official statistics: http://estatistica.azores.gov.pt:81/ReportServer/Pages/ReportViewer.aspx?%2fRelatorios+Ad+hoc+Externos%2f%C3%81gua+Energia+e+Ambiente+I-EnergiaProduzida+L-Ano+C-regiao-distrito-Origem+20160512+011028 webvideo from 2012 at https://www.youtube.com/watch?v=SXxvYvWZ5fg — Preceding unsigned comment added by 188.37.154.97 (talk) 01:16, 12 May 2016 (UTC)

Wave Energy Formula is Just Plain Wrong
The formula at the top of the page gives the result of 36kW/m for a 3m high wave with an 8 second period. This dodgy formula has been 'verified' so it has been included in Wikipedia

This is clearly wrong because a 1m high wave with a period of 10 seconds is calculated to be 40kW/m in professor David Mackay's Book Sustainable Energy - without the hot air.

http://www.inference.phy.cam.ac.uk/withouthotair/cF/page_309.shtml

Wikipedia has been carrying this dodgy formula for years without challenge and any attempts to change it has been reversed. — Preceding unsigned comment added by Andrew H Mackay (talk • contribs) 16:15, 7 April 2012 (UTC)


 * There is no contradiction: in Prof. MacKay's book, page 309, h is the amplitude, not the wave height. So the wave height is twice the amplitude: 2 m. Further his power formula is for periodic waves, while real sea waves are random waves. Accordingly, the significant wave height is about √2 times the height of the equivalent periodic wave having the same energy flux, that is 2√2≈2.8 m. The rest of the difference between 36 and 40 kW/m are due to the differences in wave height and period for the example here and in Prof. MacKay's book. -- Crowsnest (talk) 20:51, 7 April 2012 (UTC)

I do not understand why my edits are been reverted I wrote this - what on earth is wrong with this - other companies have had their entries accepted.

"Wave energy is converted directly into heat in the first instance and stored as heat on board the mobile platform or ship. The thermal power is transferred to shore based facility where it is converted into continuous base load or load following electricity. The resource to wire efficiency is 48% at a rating of 80kW(e)/metre wavefront delivering electricity with flash desalinated water as a by-product." — Preceding unsigned comment added by Andrew H Mackay (talk • contribs) 19:23, 7 April 2012 (UTC)


 * That has been stated in the edit summaries of the reverts: contributions to Wikipedia have to be verifiable by reliable secondary sources (WP:RS and WP:PSTS), and need to have due weight (WP:UNDUE). -- Crowsnest (talk) 20:51, 7 April 2012 (UTC)

My contribution is being blocked for no good reason. Why is a conflict of interest? Is there any body out there who actually reads this stuff? Andrew H Mackay (talk) 22:24, 7 April 2012 (UTC)

If I am not allowed to inform wikipedia about Gentec WaTS why are other devices allowed to 'advertise' it is either all or nothing to be fair. I am not being controversial but why do you allow free advertising for some and not others? — Preceding unsigned comment added by Andrew H Mackay (talk • contribs) 22:31, 7 April 2012 (UTC)

Wikipedia is a JOKE
You appear to only accept stuff that has been verified by academia and assume that they are always correct. Your page on wave power is riddled with mistakes in formulae that has been 'verified' by idiots. Andrew H Mackay (talk) 22:48, 7 April 2012 (UTC)
 * Hey now, no attacks on Wikipedia! bd2412  T 17:19, 1 September 2017 (UTC)

The wave formulae on this page is wrong
It is well understood that the power flux in a 1 metre high wave is 40kW/m and that the formula for calculating it is 1/4 rho.g.h^2.v so that for the 3m high wave with a period of 8 seconds in the example works out at 1/4x1025x9.81x3x3x12.49 = 282.589kW/m and not ~36kW on the page. This puts the calculation on Wikipedia out by a factor of nearly 8 times. The calculation for group velocity is wrong too; it should be gT/(2xpi) not gT/(4xpi) as stated in the article.

But you will probably carry on with this dodgy formula as you have done for several years because it has been 'verified' in a book written by some academic idiots but my calculations can be verified too by Professor David MacKay who is not an idiot and knows what he is talking about.

http://www.inference.phy.cam.ac.uk/withouthotair/cF/page_309.shtml

Andrew H Mackay (talk) 10:26, 8 April 2012 (UTC)


 * Well, these "some academic idiots" include Osborne Reynolds, Lord Rayleigh and many thereafter.
 * Did you read my previous comment on this? And read the link you give, page 309 of Prof. MacKay's book: ''"... it travels at a speed called the group velocity, which for deep-water waves is half of the speed v. You can see that the energy travels slower than the crests by chucking a pebble in a pond and watching the expanding waves carefully. What this means is that equation (F.4) is wrong: we need to halve it." -- Crowsnest (talk) 13:00, 8 April 2012 (UTC)

Three word phrase rejected for no good reason!
This is ridiculous - I inserted the phrase 'inclined artificial beach' and it was rejected - why am I not allowed to edit ANYTHING? What specifically was wrong with adding that phrase? This is a 'closed shop' to outside editors and Wikipedia has lost its way as a result.

Andrew H Mackay (talk) 15:57, 8 April 2012 (UTC)

Wrong formula
I do not know how to reply to your ludicrous answer that Prof Mackay's 40kW/m for 1m high wave from crest to trough, with a 10 second, is in line with the formula in Wikipedia that says that a 3m high wave, from crest to trough with an 8 second period contains 4kW/m less. Read the text and you will see that he is using the term 'h' to aid his centroid calculations as even if he was confused with amplitude and height, which I am not, his answer for a 3m wave 8s period would either be 353kW/m or 88kW/m so how do you explain the calculation result on the page of ~ 36kW/m if there is no conflict. So you are wrong - time to wake up to the fact that somewhere back in the dim and distant past some academic made a mistake that was verified by somebody who did not do a decent peer review and this error has crept in to the European wave energy industry's calculations. The US and the rest of the world use David MacKay's formula which is also wrong but it it a lot closer to the correct value of ~50kW/m for a 1 metre high wave 10s period.

Andrew H Mackay (talk) 16:23, 8 April 2012 (UTC)

Wave Energy Formula is Just Plain Wrong
Another point you try to make was also wrong the 36kW/m on the page related to a 3m high wave yet you compared this to David MacKay's result for a 1m high wave - do you notice the difference between the two heights? Your patronising contribution does not say very much at all!

Andrew H Mackay (talk) 18:33, 8 April 2012 (UTC)
 * Again: David MacKay is talking about an (semi) amplitude h, the "Wave power" article about wave height H which is twice the amplitude: H=2h (so 2 m wave height in the case from MacKay's book). Further Prof. MacKay describes sinusoidal waves, and the "Wave power" article irregular sea waves with a significant wave height Hs. The significant wave height is the average of the higher waves in the irregular sea. The wave height representative for use in energy (and power) calculations is the RMS wave height, so for MacKay's example HRMS=2 m. The corresponding significant wave height is √2≈1.4 times the RMS wave height, so Hs=2.8 m for MacKay's example. Which is very close to the 3 m significant wave height in the "Wave power" article. The subsequent differences between the 36 kW/m' and 40 kW/m' in respectively the WP article and MacKay's book are due to the differences between the wave periods, 10 and 8 s, and small wave-height differences in both cases: 36x(2.8/3)2x(10/8)=39.2 kW/m'. -- Crowsnest (talk) 10:29, 9 April 2012 (UTC)

So it is a closed shop
Just as I suspected these editors have allowed their own wave energy converters free 'advertising space' on the page and reject all newcomers. My description is not loaded in any way and describes exactly how it works - are you saying that all the other wec entries are made by third parties? I do not think so. There should be either no entries at all or entries open to all newcomers.

BTW my wave system, when built, will generate constant base load, and/or load following electricity 24-7 at a rating of 255kW(e)/m of wavefront because I do not convert the averaged wave power directly into intermittent random pulses of electricity like the rest and generate just @ 5kW(e)/m.

This is the real reason behind these rejections.

Andrew H Mackay (talk) 08:42, 9 April 2012 (UTC)

I have already said that the Wave Energy Formula is just plain Wrong
I cannot believe that somebody can say that there is no problem with the wave energy

Here it is again in plain English the worked example on the Wiki page gives the result of 36kW/m for a 3 metre high wave with an 8 second period - do you agree?

Using Professor Mackay's formula for a 3 metre high wave with an 8 second period gives a result of 0.25 x 3^2 x 1025 x 9.81 x 12.49 = 282.6kW/m not 36kW/m in the article. Even if you use the amplitude as the 'height' 'by mistake' you will get 0.25 x 6^2 x 1025 x 9.81 x 12.49 = 1130kW/m not 36kW/m.

How can this editor say that there is no conflict between the two. Show me how you get Mackay's formula to give 36kW/m for a 3m high wave with a 8 second period!

There is nothing wrong with my maths - even Prof Mackay's maths is wrong he should have pi in his denominator NOT 4 but we will go with his formula to avoid even more confusion.

Andrew H Mackay (talk) 17:21, 9 April 2012 (UTC)


 * The significant wave height is 3 m, so the RMS wave height is 3 / √2 = 2.12 m. The corresponding amplitude (h) is 2.12 / 2 ≈ 1.06 m. The phase speed v for an 8-second wave is gT/ (2π) = 9.8 × 8 / (2π) = 12.5 m/s. So according to the formula in MacKay's book the wave power is P = ¼ ρ g h2 v = ¼ × 1025 × 9.8 × 1.062 × 12.5 W/m' = 35.3 kW/m'. The difference with 36 kW/m' is due to round-off in the factor 0.5 kW/(m³ s) mentioned in the "Wave power" article.
 * So there are errors in your math. It is surprising you found out there are errors in Prof. MacKay's math, and with him in the math of Osborne Reynolds, Lord Rayleigh and hundreds of wave experts thereafter. That is original research. However, Wikipedia is an encyclopedia, not publishing original research. The function of Wikipedia is to present notable material published in reliable secondary sources. I advise you to publish your research, and promote your invention, elsewhere. If that results in reliable secondary sources and publicity, you may have a better chance to have your material included here. -- Crowsnest (talk) 20:41, 9 April 2012 (UTC)

I note that the wave formulae on this page is still wrong
According to professor David MacKay's formulae a 3m high wave with a 8 second velocity will have a group velocity of gT/2pi = 12.49m/s

Therefore a 3m high, 8s wave is calculated to be 282.58kW/m and NOT just 36kW/m. The answer in the article is around 8 times TOO SMALL. Time it was corrected I think.

BTW The notes show that the group velocity is gT/4pi not gT/2pi so that needs to be corrected too. Your calculation conveniently uses gT/2pi whilst ignoring the fact that the diagram has a typo where 'h' should read 'a'

Greenheatman (talk) 09:39, 13 April 2012 (UTC)

Wave energy flux formula appears illogical
The current formula states that the energy flux is proportional to T the period between waves expressed in s/wave. This leads to the very strange result that the less often a wave passes, the higher the system power. That does not appear logical.

Hello,

I see a lot of discussion about the wave power formula on this page. I feel a bit guilty as I once proposed a change to the formula. But a further change made it less clear. Maybe I can shed some light on the matter.

The formula is now wrong in the sense that it mixes a wave height definition of an irregular wave field Hm0 with a wave period definition of a regular wave field, T. This actually does not make much sense!

The factor with 1/64 (that I once proposed) refers to an irregular wave period. The wave period used to obtain the factor 1/64 is T_{m-1,0} the sometimes called wave-energy period, which is equal to the -1^th moment of the wave energy spectrum m_{-1} divided by the zeroth moment m_0. where m_n = int_0^inf{S*f^n}df, S is variance density spectrum of the water surface elevation, and f is frequency. For a normal JONSWAP spectrum the Tm-1,0 is related to the better known T_p by Tm-1,0 ~= Tp/1.1. Advantage of using Tm-1,0 is that then the wave energy formula is correct for each spectral shape! (as long as you consider deep water, and linear wave theory) If you change the formula to the definition for a regular wave field (using H and T) then the 1/64 should change. But real oceans hardly every have regular waves (maybe swell sometimes), so is not of much use. If you need a reference: D.V. Evans, 1981, Annual review of fluid mechanics 13, p157-187.

My proposal: add the -1,0 as a subscript to the T.

Cheers,

Bas — Preceding unsigned comment added by 136.231.168.49 (talk) 08:05, 28 August 2013 (UTC)

Errors in Wave Energy/Power Formulas
Dear all,

I hope I can clear up the confusion about the sections "Wave power formula" and "Wave energy and wave-energy flux":

For a  single, monochromatic wave, the wave energy flux per crest-length is [1]

P = \frac{\rho g^2}{32\pi} H^2 T_e \approx \left(957.3 \frac{\text{W}}{\text{m}^3 \cdot \text{s}} \right) H^2\; T_e, $$ with wave height H. This gives for a wave with height H=3m and period T=8s

P \approx 957.3 \frac{\text{W}}{\text{m}^3 \cdot \text{s}} (3 \cdot \text{m})^2 (8 \cdot \text{s}) \approx 68.9 \frac{\text{kW}}{\text{m}}. $$ In the ocean, the waves are irregular, i.e. they can be viewed as a superposition of many regular, monochromatic waves, which have different parameters (thus also different wave heights). To still be able to use the above formulas, a wave height which is representative for the energy within the waves has to be used in the above formulas. Different approaches exist for this; for a narrow-banded wave-spectrum for example, the following approximation can be made [2]

H = H_{m0}/\sqrt{2} , $$ where Hm0 is the significant wave height. Thus, the wave energy flux per crest-length is

P = \frac{\rho g^2}{64\pi} H_{m0}^2 T_e \approx \left(0.5 \frac{\text{kW}}{\text{m}^3 \cdot \text{s}} \right) H_{m0}^2\; T_e, $$ and thus the calculation amounts to

P \approx 0.5 \frac{\text{kW}}{\text{m}^3 \cdot \text{s}} (3 \cdot \text{m})^2 (8 \cdot \text{s}) \approx 36 \frac{\text{kW}}{\text{m}}. $$

Furthermore, there is a typo in the formula for the energy density; however the corresponding formula in section "Properties of gravity waves on the surface of deep water, shallow water and at intermediate depth, according to linear wave theory" is correct.

Since I think one should give both the formulation for a single wave, as well as for a narrow-banded wave spectrum, this is what the formulas should look like [1][2]

\displaystyle E = \frac{1}{8} \rho g H^2, $$ for a monochromatic wave, and for a narrow-banded wave-spectrum

\displaystyle E = \frac{1}{16} \rho g H_{m0}^2. $$ Hope this helps.

References:

[1]Graw, K.-U.: Wellenenergie - eine hydromechanische Analyse, Bericht Nr. 8, Institut für Grundbau, Abfall- und Wasserwesen, Bergische Universität - Gesamthochschule Wuppertal, ISSN 0179-9444, 1995.

[2]Lloyd, A. R. J. M. "Seakeeping: ship behaviour in rough weather." (1989).

Rey42 (talk) 14:28, 14 August 2014 (UTC)

Wave energy formulas have been changed on the wiki page
I agree to the formulas written in the section above (By Rey42) as true as long as the usage of H_{m0}^2 is correct, i agree to the definition of H_{m0}^2.

On a more serious note, the wave energy formulas was this summer changed away from the above derivation to: $$E=\frac{1}{8}\rho g H_{m0}^2,$$ without explaining anything.

Someone should change this back, I know there have been many arguments what the wave equation is, and the one that is present on the wiki page at the moment is for sure wrong. — Preceding unsigned comment added by Arpedk (talk • contribs) 10:56, 17 December 2014 (UTC)

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wave-power systems from CorPower Ocean (Sweden) since 2016, much more efficient than older systems, should be mentioned
The article should add a passage about the wave-power systems from swedish company CorPower Ocean: C3 Wave Energy Converter, WEC. They are described for instance in this article: https://inhabitat.com/new-swedish-wave-energy-buoy-boasts-5x-the-output-of-existing-technology/?variation=c&fbclid=IwAR0eDra4xyMTX91uXvgtAjYAqiGnyaIdCq-deaJYN0wTaWOeO9bg2YJZzRY. For instance Scotland has already anchored serveral of these high efficient buoys. --2A02:810D:A33F:F444:D9D0:10D7:8EFB:5346 (talk) 15:15, 25 January 2020 (UTC)