May 19, 2011By Kayla Purvis
In my Current Issues class at Champlain Valley Union High School, we have been looking at sustainability. We watched the movie “Earth 2100,” a supposedly scientific prediction of Earth’s future if we continue living the way we do. Despite my thoughts on that claim and on global warming itself, one thing in that movie got me thinking. The movie mentions the town of Greensburg, Kan., a town that was hit by an EF-5 tornado in 2007. In “Earth 2100,” the town is completely self-sustaining. The town of Greensburg’s “sustainable master plan” can be found on its website, www.greensburgks.org.
So, I started wondering how hard and/or easy it would be to make my own future house completely or nearly completely self-sustaining. Between wind, solar, and hydropower, how hard could it be? Then I got to wondering, if Vermont were its own country, could it manage self-sustainability?
Vermont is No. 1 on Greenopia’s list of greenest states! We have earned the following to achieve that ranking: air quality, recycling rate, renewable energy usage, LEED buildings, per capita emissions, per capita energy consumption, and per capita waste generation (www.greenopia.com). We also ranked No. 1 on “Huffington Post’s” list.
According to vermontyankee.com, Vermont Yankee puts out 650 megawatts of power, which they claim is about 80 percent of Vermont’s total energy demand. They also provide about one-third of our total electricity demand. So, if the plant is closed in 2012, I think the only sane solution is to use strictly renewable energy resources to replace all that power.
General Electric makes a common 1.5-megawatt wind turbine model. Most turbines only put out 15 to 30 percent of their total capacity because of variability in weather conditions. So, let’s assume that a 1.5MW turbine puts out 30 percent of its capacity … that’s .5MW, or 500,000 watts. Vermont Yankee’s 650MW was about 80 percent of our power, so we would at least need to match that. At 500,000 watts per one turbine, we would need 1,300 1.5MW turbines operating at a consistent 30 percent capacity in order to match the power we would lose from Vermont Yankee.
I had a bit of trouble finding the cost of one of these turbines, so I asked (Observer Liberally Speaking columnist) Steve (Mount) if he knew. One rate that he found was about $2/megawatt. Going with that, one 1.5MW turbine would be about $3 million. One thousand and three hundred of those would be, assuming no discounts, $3.9 billion. Aside from the sheer cost alone, tourism would be another hurdle. Vermont’s landscapes, views, foliage, and skiing are our major tourism attractions. How much would 1,300-or-more turbines affect that? Personally, I think wind farms are fascinating; you really don’t realize how big they are until you go past them. I don’t think that wind farms would hurt our tourism very much.
Another option would be hydropower. I did a little research and found that two gallons per minute is a pretty standard water flow to require for decent hydropower. Lake Champlain’s average rate of flow into the St. Lawrence River is 12,000 cubic feet per second, or 5,373,134 gallons per minute. To find out how many watts we could get out of that rate of flow, I converted gallons per minute to horsepower, and then horsepower to watts. One horsepower (hp) is 3,960 gpm. One horsepower also equals about 750 watts. The number I got was 1,017,639 watts. So, in theory, Lake Champlain could give us more than one million watts of electricity in one single minute. In one day, that is 1.44 billion watts.
Wind and waterpower would be great alternatives to Vermont Yankee, but they would also be expensive. I found an estimate that put the cost at about $20,000 for a hydro pump that can power a handful of modern homes. Nuclear power is clean, but can be risky. We also have to factor in whether or not it’s worth it to lose all the jobs that are provided to Vermonters from the power plant. I think it would be really cool if Vermont could find a way to get most of its power from renewable energy sources that have minimal threats and risks.
Williston resident Kayla Purvis is a senior at Champlain Valley Union High School.