It’s a crucial question because states in the Midwest and Northeast are calculating how to meet state renewable energy requirements, which have been legislated in order to expand deployment of renewable energy and reduce the emission of greenhouse gases.
The NREL study is a big deal because the complex network of utilities, power generators and transmission lines has been built over many years, and its operations can only be changed if it can be shown to be economical and cost-effective.
NREL took on the task of measuring whether it would be possible to generate 20% or even 30% of electricity needs using wind in the Eastern interconnection. The chief conclusions of the report include the following:
• "The integration of 20 percent wind energy is technically feasible, but will require significant expansion of the transmission infrastructure and system operational changes in order for it to be realized;
• “Without transmission enhancements, substantial curtailment of wind generation would be required for all 20 percent wind scenarios studied;
• “The relative cost of aggressively expanding the existing transmission grid represents only a small portion of the total annualized costs in any of the scenarios studied;
• “Drawing wind energy from a larger geographic area makes it both less expensive and a more reliable energy source – increasing the geographic diversity of wind power projects in a given operating pool makes the aggregated wind power output more predictable and less variable;
• “Wind energy development is a highly cost-effective way to reduce carbon emissions – as more wind energy comes online, less energy from fossil-fuel burning plants is required, reducing greenhouse gas emissions;
• “Carbon emissions are reduced by similar amounts in all scenarios, indicating that transmission helps to optimize the electrical system and does not result in coal power being shipped from the Midwest to New England States;
• “Reduced fossil fuel expenditures more than pay for the increased costs of additional transmission in all high wind scenarios."
It’s difficult to read those conclusions, wonky though they are, without having a favorable view of how wind power can help solve our energy and environmental problems. The conclusions are also consistent with other studies done in the United States and Europe.
But somehow the New York Times read it differently. In its article on the study, the Times wrote: “Regardless of where the windmills are built, the projected global warming benefits are modest: a drop of about 4.5 percent in emissions, at best. If no additional wind machines are built, carbon emissions will rise…And [wind] would have only a modest impact on cutting emissions linked to global warming, the study found.”
These sentences misleadingly claim that wind would only reduce carbon dioxide emissions by about 5%. In fact, emissions would have been 28.5% higher in 2024 if today’s generation mix (about 2% wind) were used to meet growing electric demand, while achieving 20% wind can turn that massive 28.5% emissions increase into a 5% emissions reduction.
Factoring in that increase in electricity demand, carbon emissions would be reduced 25.5% in the 20% wind scenario and a whopping 37% in the 30% wind scenario, relative to where we would be in a business-as-usual scenario in 2024.
The Times article also gave valuable space to the myth that “building a better transmission system to the West would be a pathway for bringing in more coal energy,” when in reality the NREL study had found that coal generation would be drastically reduced in all scenarios.
In fact, the study found that coal generation declined by around 23% from the business-as-usual case to the 20% wind power case, and by 35% in the 30% wind case.
The magnitude of this reduction in coal use is staggering. An average coal power plant consumes half a ton of coal to produce 1 megawatt-hour (MWh) of electricity, enough to power a typical home for about a month, so cutting coal generation by 486 million MWh per year in the 20% wind case would cut coal use by around 243 million tons each year. Thirty percent wind would cut coal generation by 745 million MWh per year, saving approximately 373 million tons of coal each year.
These results should be reassuring to those who have expressed concerns that upgrading the nation’s transmission system for new wind generation will have the unintended effect of allowing additional coal- generated electricity to use those transmission lines. In fact, the combination of wind energy and new transmission is actually a highly effective tool for displacing coal generation.
The Times also said the transmission expansion necessary to meet the increased 20% wind scenario “would require spending about $93 billion in today’s dollars.” True, but as NREL noted in releasing the report, “Reduced fossil fuel expenditures more than pay for the increased costs of additional transmission in all high wind scenarios." In other words, the net economic cost, which is more relevant in terms of the economy and consumers, is zero, not $93 billion.
Building new transmission overwhelmingly makes consumers better off because it provides access to lower cost sources of energy, like wind power, and thus displaces the use of expensive fossil fuels to produce electricity.
It’s also important to remember that generating power accounts for the majority of the average consumer’s electric bill–transmission typically accounts for less than 10%. Therefore, any increase in the transmission cost will be greatly outweighed by the resulting decrease in the much more important generation costs. As has been shown in any number of studies, building transmission to access wind energy saves consumers enough money to pay for the initial investment in a matter of just a few years.
Finally, it must be noted that a New York Times blog post on the report claimed that “One of the drawbacks to wind turbines is that while they may provide a lot of energy at times, they can never be counted on to provide energy in a pinch, a characteristic called “capacity.” One need read only a few paragraphs further in the same post to learn that NREL’s study did in fact find that wind turbines do have significant capacity value, directly contradicting the first sentence of the article and its claim that that it is “never” the case.
The NREL study found that when wind turbines are spread out over a large area, the majority of the energy they produce can in fact be counted on to provide capacity. Moreover, grid operators across the country already count on wind turbines to provide capacity, and dozens of peer-reviewed studies in the U.S. and Europe have already established the fact that wind turbines provide significant capacity value.
www.nrel.gov/wind/systemsintegration/pdfs/2010/ewits_final_report.pdf
www.nrel.gov/wind/systemsintegration/pdfs/2010/ewits_executive_summary.pdf
www.nytimes.com/2010/01/21/business/energy-environment/21wind.html
www.awea.org/pubs/factsheets/Transmission_and_Consumer_Savings.pdf
www.nrel.gov/docs/fy08osti/43433.pdf
