The nation is seeking to increase the reliability of its power system amid a growing push for competition and in the face of security threats. One approach being considered is distributed generation. Distributed generation, sometimes referred to as dispersed generation, is electricity production at or near the point where power is used with little or no consideration for economies of scale.
The utility grid, on the other hand, is the large-scale production, transmission and distribution of electricity at the lowest possible cost. At the early stage of the grid, economic cost was the primary focus. But in today's society, total cost, including environmental and community impact, must be included.
In a sense, the electric power industry began with distributed generation in the days of Thomas Edison. But eventually, economies of scale led to the current centralized utility-based power system. Although many people take electricity for granted, they do not want the infrastructure in their neighborhoods - the so-called Not In My Back Yard problem. NIMBY has escalated to NOPE (Not On Planet Earth).
Unfortunately, electricity has to be produced on the planet where it is used. Distributed generation seems an alternative to the grid. Technologies can be grouped as renewable and non-renewable (mostly fossil fuels). Renewable technologies such as solar, wind, small hydro, geo- thermal and ocean wave are most environmentally friendly; they have minimal known pollution. However, except for solar and geothermal, these technologies are expensive aesthetically and economically, without the economies of scale.
How many people want a wind turbine in their back yard?
Properly designed, solar panels can be integrated into existing and new buildings, but they are very expensive and require government subsidies to be cost- effective. On the other hand, where there is sufficient open space, wind and solar energy become more economical at very large scale. This is why some utilities and energy companies are investing in large-scale wind technologies integrated with the utility grid.
Another distributed generation technology is fuel cell, which converts natural gas into electricity, heat and water with minimal environmental pollution. Fuel cells hold the ultimate hope for distributed generation. If and when it's cost-effective, it can be used to power vehicles on the roads and produce electricity when parked. When parked, vehicles will still need to be connected to the utility grid to be useful.
Under the best-case scenario, every building will have its own fuel cell generation. Unfortunately, electricity cannot be easily stored; it must be consumed while produced. Therefore, the electric load in a building will have to be matched with output. What happens when a building's power generation fails, or has more or less demand than it was sized for? How about people who cannot afford the new technology? The utility grid would become the default common carrier, much like piped and bottled water, or a telephone line and cell phone.
In today's electric infrastructure and energy industry, there are several barriers to greater adoption of technologies:
• The costs of viable distributed generation technologies are higher per kilowatt than utility grid power.
• Existing grid infrastructure is more reliable than stand-alone self-generation.
• Fuel limitations and fuel price volatility make self-generation risky.
• Large customers who could self-generate already have done so.
• Site issues such as noise, environmental impact, permit approval, aesthetics, operational, safety, regulatory and societal impact of wide-scale adoption of private generators are yet to be determined.
In the near term, distributed generation may provide premium energy where customers have zero tolerance for outages and require backup. But private generation must be cost-effective, highly reliable and environmentally friendly before significant numbers of customers will adopt it. Therefore, the utility grid will likely remain the primary means of delivering power to customers, while distributed generation may represent a niche in the market.
Victor E. Udo, of Newark, is an engineer and member of The News Journal Community Advisory Board.
© 2005 delawareonline.com/The News Journal
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