What Does Renewable Energy Look Like – Part II
10 Aug, 2009
[Approx. Read Time: 4 minutes]
Only 5,000,000 Wind Turbines?
Last week, I posted an article comparing the land areas required for Nuclear, wind and solar energies to produce an amount of energy equal to two 1600MW AREVA EPRs. This week, I believe that it might provide valuable insight to show how much area these power sources need to power the entire United States. It seems that public figure after public figure makes statements that lead the general public to believe that our entire country can be powered by renewables.
Democratic Presidential Primary Candidate Mike Gravel regularly stated during Primary Season that the entire United States could be powered by only 5 million 2.5 MW wind turbines. Only 5 million wind turbines? Although this isn’t at all possible because of issues with current technologies, and the Department of Energy states that no more than 20% of our electricity can possibly come from wind and solar, after hearing Mr. Gravel say this in all seriousness, I casually calculated the land area required to do this by using lower end figures for acreage required per wind turbine. My calculations came out that over 40% of the continuous 48 states had to be covered.
Although it was unpopular for the pro-nuclear folks last time, I’m going to again give wind and solar a little benefit of a doubt. I will use gross conservatism and assume that the United States has nothing in the way (i.e. houses, schools, roads, etc.) of putting these energy installations in place. Although, I admit that this isn’t a realistic scenario. I feel that, sadly enough, it is necessary to address since there exists a very serious discussion out there by some people that think this is a realistic solution.
(Like last time, calculations and references are at the end of the article.)
Energy Consumption in the United States
First off, the according to the Department of Energy, the United States consumes 100,000 quads (quadrillion BTUs) of energy per year. This is equal to 29,000 TWh or 29,000,000,000 MWh. Converting this to MW gives us that the United States consumes on average 3,310,502 MW (MWh per hour).
For Nuclear power, I am going to conservatively round up and assume that each reactor takes up 1 sq mile of land area. This leads to a total land area required of 2,069 sq miles. An area approximately equal to the size of Delaware.
For solar power, I’m using the previously calculated 91 sq miles per 1000 MW. This means that, in order to theoretically power our entire country with solar power, approximately 301,256 sq miles of land is required. This is equal to the approximate area of the entire Southeast Region of the country. (Florida, Georgia, Alabama, Mississippi, South Carolina, North Carolina and half of Tennessee)
Finally, for wind power I’m using the previously calculated 260 sq miles per 1000 MW. Therefore, approximately 860,731 sq miles of land area is required for wind power to theoretically power our country. This gives us a land area approximately equal to everything east of the Mississippi River. But keep in mind, calculations for wind and solar don’t take into account already existing infrastructure that will increase these estimates even more.
Calculations and References
I used the commonly accepted <1 sq mi for Nuclear power plants and rounded up to 1 sq mile to be conservative. This includes the average capacity factor for Nuclear power plants at 0.90.
3,310,502 MW/1,600 MW = 2,069 sq miles
11,000 acres / 0.19 capacity factor = 57,895 acres for 1,000 MW
57,895 acres = 91 sq mi for 1,000 MW
3,310,502 MW/1,000 MW = 3,310
3,310 x 91 sq mi = 301,256 sq mi
50,000 acres / 0.30 capacity factor = 166,667 acres for 1,000 MW
166,667 acres = 260 sq mi for 1,000 MW
3,310,502 MW/1,000 MW = 3,310
3,310 x 260 sq mi = 860,731 sq mi
1 – US Department of Energy, Office of Utility Technologies, Energy Efficiency and Renewable Energy & Electric Power Research Institute
2 – US Department of Energy, Energy Information Administration
3 – American Wind Energy Association