Electric Cars and Green Power: A Clean Energy Loop

Jim Motavalli

Jim Motavalli | Aug 12, 2016

RIFTON, NEW YORK—I’m standing in the shadow of a giant blue Allis-Chalmers hydroelectric turbine, installed in this spot on the Wallkill River circa 1920. It’s one of two, and together they (still, after nearly 100 years!) generate five megawatts—modest for a power plant, but enough juice to power 4,000 homes.

New car tech meets old hydroelectric tech, and they're both capable of zero emission. (Jim Motavalli)

Hydroelectric isn’t the first source of renewable energy that Americans think of—solar and wind are usually at the top of the list—but it’s reliable and 100 percent clean. Yes, you may have heard that the dams created for hydroelectric can be fatal to fish, and some have been taken down for that reason. This is a “run of river” facility, which doesn’t store much water, so it’s impact is less.

I’m thinking about energy because I drove up to the Hudson Valley in a 2017 Chevy Volt, the recently redesigned plug-in hybrid that offers 53 miles of all-electric range before the gas engine kicks in to provide another 300-plus. I did the whole first half on a charge I got from my garage plug. I’m like a lot of Volt owners—it’s nice to know the gas engine is there for long trips, but it’s more fun to see how much ground you can cover in zero-emission mode.

The phrase “zero emission” has to be parsed here. The Volt in battery mode produces no emissions, but a coal- or natural gas-burning plant certainly generates them. And if we’re talking lifecycle analysis that pollution has to be taken into account. This is the argument that skeptics use to debunk electric cars, and it’s a largely specious one.

Woodrow Wilson was President when this turbine was installed. (Jim Motavalli)

Even if the electricity in an electric car is produced 100 percent from a coal plant, the EV is pretty green. A battery electric becomes the equivalent of a Toyota Prius on emissions, and that isn’t bad because Priuses are partial-zero emission vehicles (PZEVs, in California’s official lingo).

Here’s another way of looking at it. According to PBS, “As it stands, a conventional Toyota Prius hybrid vehicle, which burns gasoline when its batteries are not engaged, and the all-electric Nissan Leaf produce roughly the same amount of greenhouse gas pollution: 200 grams per mile, according to data from the U.S. Department of Energy.”

A row of Volts in the Hudson Valley. (Jim Motavalli)

That stat is based on an average of electric generation in the U.S. If you’re charging in California (which has a very clean grid), the EV’s performance would be much better than that—only 100 grams per mile. In the Midwest, it’s worse (300 grams). But if your power came from that hydroelectric plant, wow, that’s a totally clean green energy loop. No emissions in the whole lifecycle.

According to the Energy Information Administration, “In 2015, renewable energy sources accounted for about 10 percent of total U.S. energy consumption and about 13 percent of electricity generation.” Renewables are growing at a tremendous clip, but they need to grow faster. Our climate depends on it.

Back to those 100-year-old turbines. Did you know that the hydroelectric power that gets no respect is actually the largest renewable source for electricity generation in the U.S. Again according to EIA, it’s responsible for six percent of total generation, but a whopping 46 percent—nearly half—of all the renewable generation.

Central Hudson's John Maserjian says the local hydro plants are part of New York's impressive 26 percent renewable generation. (Jim Motavalli) 

And it’s really, really simple. John Maserjian, a spokesman for Central Hudson, took us through the process. Water from the river is briefly held in a pond, then flows through the old brick plant to spin the turbines and generate electricity. That’s the way they did it in 1920, and with only modest updates it’s the way they do it today. Hydro was in the mix when New York State's renewable energy reached 26 percent of electric generation in 2013--a pretty good number. That same year, nukes produced 32 percent of electric power in New York.

There’s only one drawback to hydroelectric—it’s not likely to expand very much. We’ve probably dammed all the rivers we’re going to dam in the U.S. Globally, though, the picture is better—hydro grows something like three percent a year. It’s 16 percent of global electricity generation, and in 2011, 3,500 billion kilowatt-hours were generated. One-hundred sixty countries produce hydropower, from 45,000 large dams.

Yes, some of those dams—particularly in China—are very destructive, destroying irreplaceable habitat and forcing the relocation of large populations. This needs to be acknowledged. Scientific American calls China's Three Gorges Dam "an environmental catastrophe." The unfortunate fact is that all forms of energy have drawbacks, including the wind turbines that people hate to look at and complain make too much noise. The people of Cape Cod get their electricity from a filthy coal plant because some residents continue to fight a pitched battle against a proposed wind farm.

It's also important to put hydro into perspective. The individual plants tend to be small in terms of generating capacity, especially when compared to base load sources like nuclear. For instance, the Dashville hydro plant is only five megawatts. The downstate Indian Point nuclear facility, which supplies power to New York City and may be shut down, is more than 2,000 megawatts.

From here, the juice goes to the grid, which is gradually getting greener with more renewables. (Jim Motavalli photo)

So I’m driving along in my very nice $40,325 Chevy Volt, a car that rates a 10 (the best) on the feds’ fuel economy and greenhouse gas rating. It gets the fuel economy equivalent of 106 miles per gallon when it’s running on batteries, and a still-good 42 when the gas motor is operating.

Some interesting facts about the 2017 Volt. It can drive 53 miles on an electric charge, and 420 counting the gas range. If you charge regularly, you can probably go 1,000 mmiles or more between fillups. The car has battery charging on demand (just pull the paddle on the wheel), and location-based charging--your vehicle knows when it's home. The Volt takes 4.5 hours to recharge on 240 volts, and 13 with the (included) 110-volt cord. But unless you're a long-distance commuter your battery will just need topping off. I recharged from a home outlet in only a few hours. Oh, and there's on-board 4G LTE Wi-Fi, so you've got a portable hotspot.

Chevrolet just sold its 100,000th Volt, a car that started from a sketch on a napkin, and shepherded into production circa late 2010 by Bob Lutz, a former executive who doesn’t believe that climate change is real. Now Lutz is shoehorning hybrid drivetrains into big Chevy trucks, and big V-8s into what were plug-in hybrid Fiskers. It’s an unusual world, isn’t it?


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