Tuesday, 12 May 2015

“Solar energy has a very broad implication. It falls over the entire earth. It’s very decentralized. If energy can be picked up from any point on the Earth, it suggests to you that you don’t need central mechanisms; that you can produce important things at a local level.” Thus “the Sun says ‘freedom.’ ”

There is growing interest in the local provision of energy:
Futures Forum: What are the most efficient forms of energy.. at a local level?
Futures Forum: Small-scale, locally-controlled power generation
Futures Forum: Local energy can be very profitable: "Seizing the opportunity of decentralised energy generation can provide new income streams for communities and councils."
Futures Forum: The Role of District Heating in our Future... Exeter & East Devon Low Carbon Task Force to address Transition Exeter meeting... Tues 11th November
Futures Forum: Local authority and community energy projects are going to pose “a big challenge" to the Big Six providers

As noted in this commentary:

In a final irony, nobody was more prescient on the need to transcend the fossil-fuel economy than that stalwart of the libertarian movement which is often dismissed as a front for Big Oil, Karl Hess. 
In the 1980 Academy Award-winning documentary Karl Hess: Toward Liberty, he observed: “Solar energy has a very broad implication. It falls over the entire earth. It’s very decentralized. If energy can be picked up from any point on the Earth, it suggests to you that you don’t need central mechanisms; that you can produce important things at a local level.” Thus “the Sun says ‘freedom.’ ”

Center for a Stateless Society » Paul Krugman Conquers the Martians
Futures Forum: Karl Hess: Neighbourhood Power: The New Localism

One supporting idea is that of DER - or, Distributed Energy Resources:

Distributed energy, also district or decentralized energy is generated or stored by a variety of small, grid-connected devices referred to as distributed energy resources (DER) or distributed energy resource systems.

Conventional power stations, such as coal-fired, gas and nuclear powered plants, as well as hydroelectric dams and large-scale solar power stations, are centralized and often require electricity to be transmitted over long distances. By contrast, DER systems are decentralized, modular and more flexible technologies, that are located close to the load they serve, albeit having capacities of only 10 megawatts (MW) or less.

DER systems typically use renewable energysources, including, but not limited to, small hydro, biomass, biogas, solar power, wind power, geothermal power and increasingly play an important role for the electric power distribution system. A grid-connected device for electricity storage can also be classified as a DER system, and is often called a distributed energy storage system (DESS). By means of an interface, DER systems can be managed and coordinated within a smart grid. Distributed generation and storage enables collection of energy from many sources and may lower environmental impacts and improve security of supply.

Economies of scale

Historically, central plants have been an integral part of the electric grid, in which large generating facilities are specifically located either close to resources or otherwise located far from populated load centers. These, in turn, supply the traditional transmission and distribution (T&D) grid that distributes bulk power to load centers and from there to consumers. These were developed when the costs of transporting fuel and integrating generating technologies into populated areas far exceeded the cost of developing T&D facilities and tariffs. Central plants are usually designed to take advantage of available economies of scale in a site-specific manner, and are built as "one-off," custom projects.

These economies of scale began to fail in the late 1960s and, by the start of the 21st century, Central Plants could arguably no longer deliver competitively cheap and reliable electricity to more remote customers through the grid, because the plants had come to cost less than the grid and had become so reliable that nearly all power failures originated in the grid.Thus, the grid had become the main driver of remote customers’ power costs and power quality problems, which became more acute as digital equipment required extremely reliable electricity.[1][2] Efficiency gains no longer come from increasing generating capacity, but from smaller units located closer to sites of demand.[3][4]

For example, coal power plants are built away from cities to prevent their heavy air pollution from affecting the populace. In addition, such plants are often built near collieries to minimize the cost of transporting coal. Hydroelectric plants are by their nature limited to operating at sites with sufficient water flow.

Low pollution is a crucial advantage of combined cycle plants that burn natural gas. The low pollution permits the plants to be near enough to a city to provide district heating and cooling.

Distributed energy resources are mass-produced, small, and less site-specific. Their development arose out of:
> concerns over perceived externalized costs of central plant generation, particularly environmental concerns,
> the increasing age, deterioration, and capacity constraints upon T&D for bulk power;
> the increasing relative economy of mass production of smaller appliances over heavy manufacturing of larger units and on-site construction;
> Along with higher relative prices for energy, higher overall complexity and total costs for regulatory oversight, tariff administration, and metering and billing.

Capital markets have come to realize that right-sized resources, for individual customers, distribution substations, or microgrids, are able to offer important but little-known economic advantages over central plants. Smaller units offered greater economies from mass-production than big ones could gain through unit size. These increased value—due to improvements in financial risk, engineering flexibility, security, and environmental quality—of these resources can often more than offset their apparent cost disadvantages.[5] DG, vis-à-vis central plants, must be justified on a life-cycle basis.[6] Unfortunately, many of the direct, and virtually all of the indirect, benefits of DG are not captured within traditional utility cash-flow accounting.[1]


Distributed generation - Wikipedia, the free encyclopedia

This info-graphic makes the ideas very clear:



Energy 101: What in the world is distributed generation? | Fresh Energy

It's happening:
WADE : World Alliance for Decentralized Energy - Localpower.org
Energy, Sustainability and Society | Full text | Decentralized electricity generation from renewable sources as a chance for local economic development: a qualitative study of two pioneer regions in Germany
Europe’s electricity industry looks to decentralize - Cogeneration & On-Site Power Production

Although, nothing's going to be perfect:
The Breakthrough Institute - Decentralized Renewables Won’t Fuel Modern Cities
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