Renewable Electricity: Poised to Make a Difference

Jun 02 - Power Engineering

Our appetite for electricity is insatiable. By 2025, global demand is projected to reach more than 26 trillion kilowatt-hours (kWh) per year. That's a lot of power, almost double the 13.6 trillion kWh the planet consumed in 2000. While most of this demand will come from the emerging economies of the world, the United States is a major player. U.S electricity demand is projected to grow from 3.6 trillion kWh in 2000 to 5.5 trillion kWh in 2025, an increase of over 50%.

The United States will need a lot more generating capacity, and quickly. Where will it come from? What balance do we strike between centralized and distributed power? And can renewable electricity make a significant contribution?

Now is the time to tackle these questions about our future electricity infrastructure. There is a national sense of urgency about energy issues, born of the recent uncertainty of both gasoline and electricity prices. Right now, people actually care about energy. This is a unique opportunity.

There is also growing interest in renewable electricity at home and abroad. In the United States, this interest is driven partly by the volatility of natural gas prices and their effect on the cost of electricity. Plus, in some areas of the country, wind power is now the cheapest electricity you can buy.

President Bush sent a major policy signal about the critical and increasing role of renewable electricity when he visited the National Renewable Energy Laboratory (NREL) earlier this year to promote his Advanced Energy Initiative, calling for a 22 percent increase in clean energy research at the Department of Energy (DOE). While many of his proposals concerned transportation technologies, the President's Initiative also laid out a strategy to lower electricity costs by shifting demand for power generation away from natural gas.

In addition to increased investments in clean-burning coal plants and nuclear power, President Bush proposed a new Solar America Initiative that would almost double the current funding for research in photovoltaic (PV) technologies. He also proposed a $5 million increase in funding for wind energy research.

The President's strategy reflects a critical truth that we in the renewable energy sector sometimes forget, because we believe so passionately in the technologies we work with every day. There is no one solution, no "silver bullet" that will solve all our energy problems. If we are to meet the phenomenal growth in demand for electricity without exacerbating climate change, the only realistic way to do that is with a diverse energy portfolio.

Energy efficiency is the most important component of this portfolio - we can make a significant dent in the demand for power by simply using energy more intelligently, not wasting it. But we also need supply-side solutions, and right now that means a mixture of predominantly coal-, gas- and nuclear-powered generation. We need to figure out how best to separate, capture and sequester the carbon in our fossil fuels so that we can use these resources without polluting the air. Additionally, we need to reinvigorate our nuclear power option by addressing concerns about waste and nonproliferation. We also need to move from a predominantly centralized model of power generation to one that includes smart, resilient, distributed energy systems.

Renewables can and should be one of the key players in meeting future demand for electricity. We have abundant renewable resources in the United States. The solar resource is good in every state except Alaska, with particularly excellent resources in the Southwest. There are enough wind resources - concentrated in hilly areas of the country, coastal regions and the Great Plains - to meet twice the country's total electricity demand. While most geothermal resources are located in the western part of the country, you can find useable biomass anywhere except in the deserts. Although hydrogen is often thought of primarily as an automotive fuel, its role as an energy carrier will be important in the electricity sector. Hydrogen can be produced from water using any available source of electricity - fossil, nuclear or renewable. This makes it possible to overcome the intermittency of wind or solar resources by using them to produce and store hydrogen, which can then be used to run a generator on demand.

Our challenge is to bring down the cost of electricity from renewable technologies in order to speed up their adoption. NREL and its industry and university partners have made impressive progress in this area over the past three decades but we still have a long way to go before all of the renewable technologies are cost- competitive with traditional alternatives. Our cost-reduction strategy takes a two-pronged approach. One is to work diligently on short-term applied R&D to bring down the cost of existing processes and manufacturing methods. The other is to continue the long-range, high-risk basic research that industry can't afford, to identify and develop the next generation of renewable energy technologies. Our new, 71,000square-foot Science & Technology Facility, to be completed this year, will allow us to do even more of this "transformational" R&D in solar, basic science and hydrogen research.

Solar technologies have seen dramatic cost reductions since NREL opened its doors in 1977. In real terms, electricity from PV costs one-fifth of what it did in 1980 and concentrating solar power costs one -eventh of what it did then. The price of powerfrom grid- connected PV systems today ranges from 15 to 32 cents/kWh, and we expect to bring that down to around 4 to 6 cents/kWh by 2025 - by developing better manufacturing techniques, higher efficiency devices and new solar nanomaterials. Concentrating solar power may even be slightly cheaper than that. Solar technologies have the potential to shift a large proportion of daytime peak loads away from natural-gas-fired generators.

In the best wind regimes, wind-generated electricity today costs about 4 to 6 cents/kWh-one-tenth of what it did in 1980. Our scientists and industry partners at the National Wind Technology Center expect to bring that cost down to 3.6 cents/kWh at low windspeed sites onshore by 2012 and down to 5 cents/kWh for shallow water offshore sites by 2014. Their work today is focused on developing efficient low wind-speed turbines, advanced power electronics and transferring wind technology to off-shore systems. With accurate forecasting techniques, wind energy has the potential to displace up to 20 percent of the electricity grid's baseload generation.

Biopower today costs 8 to 12 cents/kWh, half of what it cost in 1980 and we expect to bring that down to 6 to 7 cents/kWh by 2020. Electricity from geothermal resources costs 5 to 8 cents/ kWh today, about one-third of the cost in 1980 and is projected to drop to less than 4 cents/kWh by 2025.

Renewable electricity can make critical contributions to our nation's energy future, but only if we bring together the new technologies with the markets and policies necessary to accelerate their acceptance and use. The time is right, the opportunity is there - we must make the most of it now.

BY: DAN ARVIZU. PH.D., DIRECTOR, NATIONAL RENEWABLE ENERGY LABORATORY