Talk:Distributed generation

Off topic
I was actually redirected to this page, having searched for District Energy - a good page I referred to yesterday. This Distributed Power page does not cover the district energy topic, except in passing; instead it seems to push an agenda of distributed generation - related, and arguable laudable, but definitely *not* the topic of district energy. IanGTheaker (talk) 16:21, 23 December 2009 (UTC)

A lot of the links on this page do not refer to Distributed power, as described in the article but refer to Renewable energy and other topics, such as Domotics or domestic robotics and Power appliance remote control or Power line communication. As I understand Distributed power, it involves the production of electricity by consumers for transmission to other consumers nearby. -- kiwiinapanic 10:44 14 Jun 2003 (UTC)

Your article on Distributed power would be more accurately titled Distributed generation. It is an article which fits well into the series of articles on electricity, electricity market, electric power transmission, electricity generation, and electricity distribution. Distributed power is more about the distribution of power whereas "distributed generation" is a topical subject associated with how local generation can contribute to how future electricity needs can be met, including from renewable energy sources. I agree with kiwiinapanic that there are too many unrelated links. I would be happy to cooperate with you on the article, if you wish. Tiles 05:49 15 Jun 2003 (UTC)

Plagarism
This page is directly plagarized from page 26 of "Electric Power Industry" by Denise Warkentin-Glenn. 01:23 31 Jan 2007


 * The anonymous editor is correct, I found the book on Google Print, and many parts of this article were a cut/paste copyvio. I'm trying to determine if there's enough left to salvage, or if it should be deleted. Seraphimblade 06:29, 31 January 2007 (UTC)

Executive Summary
Distributed energy resources are a variety of small, modular power generating technologies that can be combined with energy management and storage systems and used to improve the operation of the electricity delivery system. It is evident that Technology options for distributed generation are abundant, and improving. Employing distributed generation can be as simple as installing a small electricity generator to provide backup power at an electricity consumers site, or it can be a more complex system that is highly integrated with the electricity grid and consists of electricity generation and energy storage. Distributed power has a wide range of benefits to both consumers and power providers, and many of these benefits are currently difficult to measure. Combined heat and power, energy storage, and energy efficiency measures can be integrated with distributed generators to increase the economic value, and enhance the other benefits, of distributed power systems. As there is the potential for major portion of the electricity power supply to come from decentralised power sources, billing and energy credits, generation control and system stability remain significant issues limiting the widespread use of this technology.

Introduction
In the United Kingdom, large generator stations are the main producers of electricity; the plants are powered largely by coal or other fossil fuels. “The market for small-scale distributed power generation is being driven by a trend of rising and increasingly volatile fossil fuel prices, the rising concern for power quality / reliability and environmental concerns [1]” Distributed power generation is a new concept in the electricity sector that provides electric power at a site closer to the customers than a central station generation. The generators are relatively small which are at or near the end users, typically ranging in capacities from a couple of kilowatts up to fifty megawatts. The key factors that are pushing the market forward are: market liberalisation and environmental concerns. “Customers usually own the small-scale, on-site power generators, but they may be owned and operated by a third party. If the distributed generator does not provide 100% of the customer's energy needs at all times, it can be used in conjunction with a distributed energy storage device or a connection with the local grid for backup power.” [2] Distributed power technologies are smaller, efficient and cleaner than centralised power system. They can provide reliable and uninterrupted quality power; have peak shaving capabilities, standby generation, base load generation, cogeneration (the production of electricity using waste heat, as in steam, from an industrial process or the use of steam from electric power generation as a source of heat) and meet cooling and heating needs. Various technologies are available for distributed generation, including turbine generators, internal combustion engine/ generators, micro-turbines, photovoltaic/solar panels, wind turbines, and fuel cells. The new technology also improves the efficiency of waste heat in combined heat and power (CHP) applications, which also lowers emissions. “CHP systems provide electricity, hot water, heat for industrial processes, space heating and cooling, refrigeration, and humidity control to improve indoor air quality and comfort”. [3]

Current status
Distributed generation refers to the production of electricity at or near the place of consumption. Examples of distributed generation include backup generators at hospitals, photovoltaic systems on residential rooftops, and combined heat and power (CHP) systems in industrial plants or on university campuses. Although some types of distributed generators have been around for many years, the earliest generators were largely distributed in the sense that they were located near the points of consumption, total customer owned generation as a percentage of all output is very small. There are three main characteristics that differentiate most distributed generation from traditional electricity supply, they are:- 1.	Location 2.	Capacity 3.	Grid connection

Location
They are typically on site generators; they are used to meet a portion of the customer’s demands or to provide backup service for customers that need highly reliable power. Applications of small scale distributed generation could include CHP for universities to generate electricity on campus and then use waste steam from the boiler to heat buildings. Electric utilities can also install their own small generators near consumer, in order to relieve congestion in power lines during peak demands. They may also be used to boost the quality and reliability of local electricity service by providing voltage control and backup power to customers.

Capacity
The size of customer owned units, which are mostly used to meet onsite requirements, typically range from a few kilowatts to a several hundred kilowatts. Generators in that ranges of power are normally best suited to applications that meet the energy demands of individual homes and businesses or of small groups of customers.

Grid connection
Traditional suppliers are connected to the grid at a transmission level. If distributed generation came in to widespread use, most distributed generators would be connected to the grid at the distribution level, which is the portion of the delivery network, built with limited capacity.

I don't know if here is the place to ask the question, but How do they solve security problems of connecting to the grid? I mean, How do they make sure there is not electricity to do the maintenance in the transmission system? There should be a solution I would like to know how it works. --Nachoj (talk) 20:44, 6 May 2008 (UTC)

What are the options?
There are many technologies available that are suited to small distributed generation applications. Among the technologies fuelled by fossil energy are conventional steam turbines, combustion turbines, internal combustion engine generators, micro-turbines and fuel cells. The renewable technologies are photovoltaic cells, wind powered generators and biomass fuelled generators.

Steam turbines
Conventional steam turbines and combustion turbines are well-developed technologies that are widely used for medium sized systems (more than 500 kilowatts). The turbines produce low emissions, give standard control equipment, and they have low maintenance and operating costs relative to those of most other generating technologies. Those characteristics, along with the short lead times needed to build units, makes them the preferred technology for most conventional generation applications requiring more than several megawatts of power.[5]

Internal Combustion engines
Internal combustion engine generators, including diesel cycle and spark ignition motors, are the most commonly used technology providing backup power for reliability or emergency supply purposes. Units range in size from 5 kilowatts to 7 megawatts. They can burn refined petroleum products, namely, diesel and gasoline or natural gas. These engines drive the vast majority of onsite generation. They are mass produced by many manufactures around the world, cost less than other distributed generation technologies, and have a fully developed sales, maintenance, and repair infrastructure. All of these factors combined with market familiarity, decreasing exhaust emissions, extended service intervals, and long engine life, continue to make engines the most commonly distributed generation technology. [4]

Microturbines
Microturbines are small combustion turbine generators that were developed on the bases of the turbocharger technology used in trucks and airplanes. The capacity range of micro turbines is 30 kW to 400 kW, covers the average load requirements (consumption needs) of most commercial and light industrial customers. Micro turbines have low emissions of pollutants, especially nitrogen oxides, which would permit there insulation in urban areas with restricted emissions standards. Microturbines became commercially available in 1998. Although they are slightly higher initial costs, they are currently the most cost effective alternative to reciprocating engines for small scale generation. They operate on the same basic thermodynamic principle as the conventional gas turbine. However they are much smaller than gas turbines, with output measured in the tens and hundreds of kilowatts, rather than megawatts. [4]

Fuel cells
Fuel cells use an advance electrochemical process to generate electricity. The process is comparable to that used in conventional batteries, except that the reactant material in fuel cells can be replenished so that the units will not run down. Fuel cells produce virtually no emissions of air pollutants or green house gases. Because there costs per installed kilowatt are still high relative to those of conventional technology, commercially available fuel cells currently suite only very specialised applications. But some companies have developed new fuel cell technology that project will lower costs significantly[6].Noise from fuel cells is very low compared with other distributed generation technology, and it generally only comes from air blowers and water pumps in the cooling module. Fuel cell systems can also use waste heat to boost thermal efficiency to 80 percent or higher. [4] There are several different types of fuel cells, namely by the type of electrolyte they use:- •	Phosphoric acid •	Proton exchange membrane •	Solid oxide •	Molten carbonate •	Alkaline

Photovoltaic
Photovoltaic cells convert sunlight into an electrical current. A panel of semiconductor material sandwich between two conducting layers absorbs solar energy and releases electrons to produce the current. Photovoltaic systems can be small, which is why they can easily be used on houses. Photovoltaic cells produce no direct emissions, and they have low maintenance requirements. Improvements in the manufacturing processes have reduced the costs of this technology significantly in the past decade. But still, the acquisition and installation costs of the photovoltaic system are approximately ten times greater than those of conventional systems. [5]

Future Aspects for fuel cells
Fuel cells may capture a significant part of the distributed generation market as technology in proven and costs are reduced. This may be proven by:-

•	Different fuel cell types for different applications •	High efficiency •	Power quality and reliability •	Low emissions •	A link to renewable fuels •	Low energy service costs

Costs
The difference in costs cost and performance among the distributed generation technologies:- Capacity (kW)	Capital cost ( £ / kW)	Electrical efficiency %	Maintenance ( £ / kWh) Micro-turbine 	30-25	300 - 600	25 - 30	0.015 Fuel cell	~200	~2000	40 - 70	0.01 photovoltaic	~100	~3500	NA	0.005 internal combustion engine	~5000	300 - 600	25 - 45	0.006 Industrial gas turbines	500-MW	200 - 400	15 - 35	0.018 Stirling engine	100 - MW	~4000	15 -25	0.018 Source: BC hydro, Power smart for business / Investigate energy Management tools, based on data from Platts (research and Consultants) The direct costs of distributed generation include:- •	Installation costs of equipment •	Fuel costs •	Non-fuel operation •	maintenance expenses “The cost of acquiring and installing a generating unit vary widely, depending on technology and capacity. Among small capacity technologies, internal combustion engines have the lowest capital costs and the highest capital costs. Renewable technologies have the highest capital costs and the lowest operating costs. New high efficiency technologies, such as micro turbines and fuel cells, fall in between.” [3] “Capital and generation costs are not the only parameters affecting cost and choice of distributed generation systems:- •	Maturity, technical and environmental performance are critical to technology and fuel selection •	The systems must pay connection charges •	Licensed generators must pay license fees •	Delivered energy costs depend on network issues, policy and regulation” Source: Decentralised generation- technologies and Market prospects

Trends in costs
The capital and operating costs of certain distributed generation technologies have fallen significantly in the recent years and can be expected to continue to do so. In the case of one technology, photovoltaic systems, the cost per delivered kilowatt hour in suitable applications has plummeted by almost 70 percent since 1980, and it is projected to decline by another 70 percent from the current levels by 2020”. [3] It has been forecasted that fuel cells will decline in cost also improve in performance in the next few years to the point where they are applicable for widespread use. [9]

Economic Considerations
Although a comparison of typical costs for various distributed generation technologies is found to be extremely useful when considering the installation of distributed generation, there are other key factors which must be taken into thought. Distributed generation technologies differ from central power by providing better quality and money saving which in result outweighs the direct cost difference. Commercial and small industrial customers with significant hot water needs can use microturbines in combined heat and power (CHP) applications. Customers in environmentally sensitive areas can use fuel cells that produce extremely low emissions and noise. For rural applications, photovoltaic systems are ideal as they reduce the need capital spending to extend power lines to remote sites.

Utility Act 2000
‘Utility act 2000’ is a governmental legislation on energy and market liberalisation. Principles which involved: new duty on distribution businesses to facilitate completion in generation and supply. [16]

Renewable Obligation
A government target which aims is to increase the renewable electricity market by 10% near 2010; applies to all licensed suppliers as a percentage of all sales including CHP (buy out set at £3/MWh). Total obligation will represent around 32 TWh/year by 2010.

Climate Change Programme
The intentions of the government in the programme are; 20% reductions of carbon dioxide emissions by 2010 from 1990. Renewable and good quality CHP applications, which may include fuel cells, are exempt from the policy. An attractive incentive such as the formation of the ‘Carbon Trust’ was created in order to fund low carbon technologies and projects.

CHP target
DEFRA initiative. The Aim is to create 10GW good quality CHP by 2010. Exemption from CCL for good quality CHP based on energy efficiency and environmental performance of CHP plant compared to good alternative energy supply options – beneficial for FC’s. Enhanced capital allowances directed at good quality CHP.

Energy Efficiency Commitments Programme
A programme administered by Ofgem. Energy efficiency Obligations on electricity and gas suppliers could support installation of distributed generation at end users by energy suppliers. [16]

Distributed generation working group (OFGEM and DTI consultation and research group) Review and draft regulation amendments, connection and operation of distributed generation, current technical, regulatory, and commercial developments relevant to distributed generation. [11]

Government
The United Kingdom in contrast to other countries has an advanced liberalised market, which has policies that favour the development of combined heat and power (CHP) and renewable sources of energy and considers the development of distributed power generation in general as an important way to increase competition among electricity producers.

The UK Government commissioned an 'Embedded Generation Working Group' to examine the role of distributed generation in the liberalised market. The group's report, issued in January 2001, identified a number of practical measures to ensure that distributed generation is integrated into the power system in an economically efficient way. A 'Distributed Generation co-ordinating Group' has been established to follow up on the Working Group's recommendations. [9]

Social Impact
“Many of the benefits and costs of Distributed power technologies accrue to people other than those who decide to install the generators, incur its direct costs and claim its benefits. Economists like to call these effects externalities”. [14]

Failing to account for externalities is one form market failure (unless the market structure is instituted so that a full range of costs and benefits accrue to the investor of the energy generator, they are unlikely to make the optimal social investment choice.)

The Benefits
Distributed generation, operated as complement to traditionally supplied power, may offer significant benefits. It could lower the nations overall costs of producing and delivering power. It could also promote the development and use of renewable energy sources and fuel efficient technologies, which could improve the quality of the air and the security of the nations energy supply. [7] “Distributed power has a wide range of benefits to both consumers and power providers, and many of these benefits are currently difficult to measure. Combined heat and power, energy storage, and energy efficiency measures can be integrated with distributed generators to increase the economic value, and enhance the other benefits, of distributed power systems.”[4] Distributed generation offers important benefits for generation, transmission and distribution activities, the environment and the final customers as reliability and quality of power. In general, from the electricity industry perspective, the benefits include the following: [3] •	Generator can be sited close to the end-user for lower transmission distributed costs and electrical losses. •	Sites for small generators are easier to find. •	Distributed generators are more quickly planned and installed. •	Energy can be ‘stored’ as fuel (e.g., gas) and easily ‘released’ at peak times. •	The network can ‘close ranks’ if one generator is taken off-line, resulting in higher reliability. •	Newer technologies are environmentally clean (low emissions and low land impact) and not noisy. •	Newer distributed generators can run on multiple types of fuels, even bio-gas, thus increasing flexibility and reducing fuel transportation costs. •	Services and benefits that can be provided by other resources. These include spinning reserve, black start capability (micro turbines can go from cold start to full load in two minutes), load following and reactive power. From the customer point of view the benefits include the following: •	Power is readily available and offers better quality and reliability. •	Depending on the fuel used, electricity prices are often lower. •	Since the generators can be operated on command, peak shaving is possible, which reduces demand charges. •	Co-generation of heat and electricity improves the overall energy efficiency of the installation. Benefits on the environment Many environmental and energy conservation campaigners believe that distributed generation could offer significant benefits. Benefits for environmental quality may come from distributed generation’s role in promoting renewable energy sources, less polluting forms of fossil energy, and high efficiency technologies. [15] Distributed generation technologies that relied on renewable energy sources could yield environmental benefits in the form of reduced emissions of pollutants and greenhouse gases if those technologies displaced utility supplied power, much of which is generated from coal. Technologies that relied on conventional fuels would yield environmental benefits if they resulted in a shift to less polluting energy sources. High efficiency technologies could yield benefits by reducing the amount of energy required to produce a unit of electricity. [15]

The Disadvantages
- - - - Discussion: (I'm new on wikipedia and it isn¨t easy to find where this should be placed. Please move it to a better place if needed).

De-centralizing the energy production may very well lead to increased climate and local emissions as well as less investments in energy efficiency and use of waste energy.

Typical example is district heating, where centralised co-fired plants will be better in cleaning the exhausts from local emissions than small decentralised ones, where centralised plants can be placed by the water to use bulky biomass instead of having trucks delivering at every single household, where you can use the natural 4 centigrade water for district cooling, where economy of scale make it possible to use low-value heating as ground water or waste water, where you can use counter-current to produce both district heating and district cooling. A few centralised plants connected by a common grid also opens up for using waste heat from grocery stores, computer centres, industry etc.

For electrics it is almost always better to centralize than de-centralize. - windmills gathered in parks can be placed far away from cities and hence disturb much less people than decentralized - Hydropower will always ruin nature - it would be a catastrophy to close the existing big ones and decentralize it to many new small ones. Let's keep the big centralised ones we have and lets close the small ones - they are generating very little power compared to how much nature they destroy - possibly it is also better to centralize photovoltaics - using the benefits of economy of scale for maintenance and service. It might be a much better solution to use the roofs as green roofs and city gardens - green roofs reduce energy need during summer and reduce energy nedd for taking care of water after downpours.

Centuries of experience shows that having your own cheap energy production is a strong disincentive for investing in making your house more energy efficient.

By keeping the energy production centralised we can also save money by not having to invest heavily in smart grids. For some countries decentralising may be a feasible option as their grid need heavily investments - but it is not a panacea. And there is alway the option to reduce the electricity use.

- - - -

The introduction of new electricity trading rules, known as the New Electricity Trading Arrangements (NETA), have created disadvantages to small distributed generators because of higher transaction costs, requirements for balancing output against forecast, and, most importantly, because of the fall in power prices. As a consequence, NETA has led to greatly reduced power output to the grid by distributed generators. [8]

The Risks
The prospects for widespread adoption of distributed generation technologies are not all certain. Nor is it clear that those technologies will be used in ways that achieve their full potential economic benefits. Moreover, this new source of electricity poses a distinct risk of negative impacts that may be difficult to anticipate or expensive to avoid. Those effects include potential degradation in the performance of the electricity distribution network, inequitable and possibly inefficient redistribution of the costs of electricity service among customers, and a decline in environmental quality. [7]

The distributed generation technologies with the greatest market potential are probably those fuelled by fossil energy, not renewable energy. High efficiency micoturbine and fuel cell technologies are still at the early stages of commercialisation, so their potential is largely unknown. Thus, the immediate promise of improved air quality from wider adoption of distributed generation may be limited

Obstacles
Today’s distribution networks have been built to deliver power from the national transmission network to the end customers. Distribution generation, however, requires more active distribution networks which allow electricity to flow in two directions (to electricity user, and on the network when the user is exporting excess generation capacity. [12]

Conclusion
It is evident that Technology options for distributed generation are abundant, and improving. Barriers to the breakthrough Arfita (talk) 14:08, 20 July 2013 (UTC) break trough of decentralised generation are related relate to; •	Breaking the one-track centralised energy provision approach by generators, network operators and security requirements – need to change the regulations. •	Market created for centralised energy provision, small player are left out. •	Lack of cheap power electronics that will ensure network stability. •	High costs of network reinforcement. •	Regulatory uncertainty. •	Further analysis is required regarding design, operation and control of systems.

Distributed generation is expected to play a greater role in power generation over thy coming decades. There is a growing interest on the part of power consumers for installing their own generating capacity in order to take advantage of flexible distributed generation technologies to produce power during favourable times, enhance power reliability and quality, or supply heating/cooling needs. While much of this capacity generally contributes little to overall electricity production, it can be expected to become an increasingly important source of peak supply.

Safety
"The plus side is that unlike coal and hydropower, there are no pollution, mining safety or operating safety issues."

OTOH the majority of solar PV installs use lead acid batteries, which do come with operating safety issues. Tabby 03:37, 14 September 2007 (UTC)

Cost/W?
A bit confused about the prices per watt. Why don't we just use current prices of coal, instead of a figure from the 70's? NittyG (talk) 23:38, 29 June 2009 (UTC)

-Agreed User:tmcdouga

I think some numbers concerning levelized cost of electricity (LCOE) are in order. There's only one mention of LCOE at all, and it's pretty indirect (something about "levelized cost of generation" being higher for distributed generation than for other sources; further aggravated by no citation). It should be noted that LCOE takes into account basically every relevant factor, including capital costs, interest, fuel, transportation, inefficiency of transmission, disposal of wastes, and decommissioning; so it's a pretty good basis of comparison. The price of nuclear power, for instance, is hardly ever quoted in terms of anything other than LCOE, precisely because the low operational costs are misleading. Ahnrenene (talk) 00:09, 26 December 2012 (UTC)

Grid Integration
I noticed that there was very little about the challenges of integrating distributed generation with the grid, and felt that there are almost enough issues to make that an entirely new page, so I fleshed out that section a bit. I would appreciate if somebody could add a picture of the duck curve on the article outside of the link (this is my first edit and I can't upload pictures yet). I briefly addressed the challenges and benefits of several distributed generation technologies. Ee137bmademe (talk) 03:54, 29 April 2015 (UTC)

Merge proposal
Find this unfinished merge proposal on Microgrid page. Technical nomination, still don't have my own opinion. Beagel (talk) 20:00, 20 August 2010 (UTC)
 * Do not merge: Distributed Generation is about the ways to produce energy. "Microgrids" is  about how to operate a grid or a part of a lerger grid, with distributed generation as a requirement but additiohal features.
 * Sugget to skip the merge banner. —Preceding unsigned comment added by Meerwind7 (talk • contribs) 11:22, 7 November 2010 (UTC)
 * Do not merge; The article is too comprehensive to consider it as being simplistic. Such as a Voltaic (electric) solar array / wind turbine combiation that many individuals (including myself) have installed on their properties. The contributor has specified the system is multiscourced with regard to power generation, and the size of the installation cannot be considered to be domestic.


 * an aside:- Grid tie inverter and Grid-tied electrical system are suitable candidates to merge as they both describe the same thing.Francis E Williams (talk) 21:54, 30 November 2010 (UTC)

So what gives? Two votes against merging, and the article still got merged? I propose splitting. GBMorris (talk) 20:33, 2 December 2010 (UTC)
 * This article is about baking bread. All that stuff about mixing and kneading dough should be split off into another article. Really, how much of the reader's time do we want to spend on gathering increasingly tiny slivers of information out of the deep shag carpet of Wikipedia and trying to glue them together into the broken souvenier ashtray of knowledge? But if you do split it, please write it in English, not in academic thesis-ese, and give more than one reference, not just your prof's book. --Wtshymanski (talk) 21:09, 2 December 2010 (UTC)
 * Well, as stated above, Distributed Generation is about generation; Microgrids is about grid operation. A more apt analogy might be to compress the article on ovens into a sub-section in the baking bread article. I do plan to help rewrite the Microgrids article, but these things take time. Also, I'm not exactly a Wikipedia ninja... how does one unmerge articles? Thanks. GBMorris (talk) 21:33, 2 December 2010 (UTC)

"Locavolters"
Shouldn't we mention that people that produce small scall energy (for neighbourhoods, ...) are "locavolters" in the article ? See http://www.motherearthnews.com/renewable-energy/local-energy-issues.aspx and http://www.worldchanging.com/archives/008596.html KVDP (talk) 12:07, 29 July 2015 (UTC)
 * Hi there, as I see, you already created a redirecting page for Locavolt. So yes, please go ahead. Note, the above link is from 2008, so maybe something more recent would be great. -- Cheers,  R fassbind  -talk   20:14, 29 July 2015 (UTC)

microgrids should be its own page
Microgrids links here - but are a fundamentally different concept than distributed generation. How do we break this page up? --Pacegri (talk) 19:32, 13 August 2016 (UTC)