The Answer, My Friend, is Blowin’ in the Wind
Two statements regarding renewable energy contained in the Back Page interview with Steve Chu and Steve Koonin [
APS News, December 2006] deserve correction. Renewable energy (wind and solar) are dismissed for reasons that do not stand up under principles that should be well understood by your members. The statements are that “[Sequestration and nuclear] are the only technologies we know that we can scale now to the magnitudes needed,” and “…because it is a transient source, without efficient and cost effective energy storage, the base line will be nuclear power and coal in the near-term future.”
Wind power can in fact be ramped up quickly and on a large scale today, without waiting for future technological breakthroughs. Denmark currently gets 20% of its electricity from wind without “storage” or “back-up” capacity. In the U.S., a country with a vast wind resource, wind power is growing fast, and was the second-largest source of new power generation in the country in 2005 and 2006. Barriers to wind power’s growth on a large scale are regulatory, not technical, and a task force including the U.S. Department of Energy, National Renewable Energy Laboratory, American Wind Energy Association and utilities, foundations and other groups, is evaluating the goal of 20% of U.S. electricity from wind.
One of the keys to successful large-scale integration of wind are large regional electric power markets where variability of both load and generation are smoothed out and where system operators can more reliably balance electricity demand and supply. Another key is diversity in the mix of fuels used for electricity generation. Flexible generators such as natural gas-fired units and hydropower are generally much more economical than storage devices for system balancing. Third, construction of new transmission lines will be needed under any type of electricity growth scenario. A key to large-scale development of wind in the US is transmission investment to tap the vast resources of the US heartland-an investment that is quite affordable compared to that of carbon sequestration on a large scale or new networks of Liquified Natural Gas (LNG) terminals and pipelines. In fact, the authors described sequestration in their reply to the previous question as “not yet demonstrated” and of “unknown cost.”
The annual rate of growth of wind generation over the past 10 years has been 28%. Globally, there is now over 70,000 MW of wind generation in operation. There have been 10,000 MW of wind capacity installed in the US to date, and not a single megawatt of backup capacity or storage for the wind generation has been required by the power system operators. This growth in wind is supported by a young, dynamic workforce, and major manufacturing companies (GE, Siemens, Mitsubishi, Caterpillar), major financial institutions (Goldman Sachs, Morgan Stanley, Berkshire Hathaway), as well as energy companies FPL, Iberdola, EDF, Shell and even Steve Koonin’s BP.
With this demonstrated ability to scale wind generation, we can look to actual experience as well as numerous peer-reviewed studies of large-scale use of wind for answers to the authors’ concern. (See for example GE Power Systems Energy Consulting for New York State, 2005, EnerNex for Minnesota 2006.) Chu suggests that wind and other renewables require storage because they are “transient.” This misunderstanding stems from a narrow definition of the energy supply. An energy technology does not have to be “baseline” (baseload) in order to make a large contribution to electricity supply. An example is natural gas, which now accounts for close to 19% of U.S. electricity supply, about the same share as nuclear. Natural gas is mostly valued because of its flexibility in responding to peaking demand.
Wind and other technologies can make a large energy contribution to the nation’s supply even while their contribution to baseload may be modest. In wind’s case, its value is in the large amounts of energy it can deliver, and in the fact that it is clean (zero-emissions, light footprint), cost-effective (cost of electricity produced does not vary over time since there is no use of fuel), energy-efficient (wind has one of the highest energy payback ratios of any energy technology), and that it strengthens energy security (wind is domestic and inexhaustible). Moreover, wind observed and captured at a single location is variable, but within patterns that can be anticipated on a seasonal and even daily basis and are modeled with increasing accuracy. What’s more, the circulation of air around the earth is constant, driven by the constant energy of the sun. To make practical use of this simple phenomenon requires some scale, which the wind industry is capable of delivering, despite the authors’ comment to the contrary.
Wind generation is added to power grids which can span portions of continents. Energy production is more concentrated than energy consumption, and transmission is key to keeping the supply and demand of electricity in balance at all times. Chu is correct in advocating greater attention to new, high voltage transmission. The point he misses is that the distribution of wind generation across a wide region allows a much greater reliance on wind, because the variation in wind production at any one location is offset by the production at other locations. Just as the wind is necessarily always blowing somewhere, windfarms spread across the Eastern or Western Interconnection of North America can, and already do, provide large amounts of clean, economical energy and even a measurable amount of reliability, what Chu called “baseline.”
Mike Jacobs Concord, Massachusetts Ed. Note: The author is Deputy Policy Director, American Wind Energy Association