Evolution FAQs

Please click on the links below to view the answers to some of the most Frequesntly Asked Questions
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Is Climate Change Real?
The Earth's climate has changed throughout history. Just in the last 650,000 years there have been seven cycles of glacial advance and retreat, with the abrupt end of the last ice age about 7,000 years ago marking the beginning of the modern climate era - and of human civilization. Most of these climate changes are attributed to very small variations in Earth's orbit that change the amount of solar energy our planet receives.

NASA Climate Change report

Do electric vehicles help the environment?

    A cradle-to-grave analysis finds driving an electric car in California creates less greenhouse gas emissions than even the most efficient gasoline vehicle. A car running on electricity even when powerplant emissions are considered produces pollution equivalent to a theoretical conventional car with fuel economy of 87 miles per gallon, according to a study, released Thursday by the Union of Concerned Scientists.

    The organization tallied all the greenhouse gas emissions from every aspect of auto manufacturing and operations and found that electric vehicles beat their gasoline counterparts in every region of the U.S. They did best putting out the pollution of a gas vehicle that gets 135 mpg in upstate New York, which is rich with renewable energy resources. Electric cars offered the least pollution reduction the equivalent of a 35 to 36 mpg car in the central U.S., states such as Colorado, Kansas and Missouri, because so much of the electricity in that region comes from fossil fuels such as coal.

    "Although a battery electric vehicle has no tailpipe emissions, the total global warming emissions from operating it are not insignificant; they depend on the sources of the electricity that charge the vehicle's batteries and on the efficiency of the vehicle," said Rachael Nealer, a UCS scientist and the report's author.

    Nationally, electric cars produce less than half the global warming emissions of comparable gasoline-powered vehicles, even when factoring in the extra pollution over internal combustion vehicles produced manufacturing the cars mainly from the production of the big lithium-ion battery packs, the study said. Nealer said the study demonstrates that electric vehicles will be essential to achieving the deep emissions reductions by mid-century needed to avoid the worst effects of climate change.

    Nealer's report examined emissions from automobile and battery manufacturing and other factors such as how electricity is made and how much gets used up in the transmission to factories and electric cars. The report took into account emissions that come from oil extraction, refining and transportation to gas stations. Nealer relied on data produced by the Department of Energy, the Environmental Protection Agency, the Argonne National Laboratory and from auto manufacturers. "This compares the total life cycle of an electric and a similar gasoline vehicle," Nealer said.

    The scientific group based its modeling on the Nissan Leaf and Tesla Model S, the two bestselling electric cars in the U.S. Each has a different greenhouse gas emissions profile because of their batteries. The bigger the battery, the more pollution results from its production. That's why the smaller Nissan, which also has less than half the range of a Tesla, offsets its excess manufacturing emissions in about 4,900 miles, or six months of driving. The Tesla offset comes within 19,000 miles, or 16 months of operation.

    Nealer expects the emissions profile of electric cars to continue to improve over their gasoline counterparts as technology advances and electricity generation becomes cleaner. "It is really impressive how much cleaner electric cars have become in just the last three years," she said.

What is the difference between a pure electric vehicle and a plug-in hybrid vehicle?
Plug-in hybrid electric vehicles can operate on electric power for about 10-20 miles. On longer trips, plug-ins transition to gasoline/electric hybrid mode to extend their range, allowing them to drive as far as a regular hybrid, with the ability to quickly refuel at a gas station. Plug-in hybrids have unique appeal for drivers who travel mostly short distances and can therefore benefit from operating on electricity, while providing what amounts to the unlimited range potential of a gasoline engine. For example, Chevrolet Volt drivers spend most of their time in electric mode thanks to its 50-mile electric range. Research from the Idaho National Laboratory has shown that Volt owners average three-quarters of their mileage powered by just electricity.

How long does it take to charge an electric vehicle?
Charge times vary greatly, depending on the size of the battery, how fast the car is able to take the charge, and the amperage of the circuit. For most EV owners, charging overnight is the cheapest and most convenient option (much like charging a smartphone), so comparing hours when shopping isn't necessary for most applications. Unless you are pushing the range limit on a daily basis, you won't have to fill it up from empty to full very often. On a typical 240-volt (Level 2) charger, it can take between 4.5 and 6 hours to fully charge an EV. Plug-in hybrids can take significantly less time to recharge, ranging from two hours for the Toyota Prius Prime to about 4.5 hours for the Chevrolet Volt. Expect a little more than double those times when charging from a standard 110-volt (Level 1) household outlet. Put another way, on a standard household outlet, expect to get about four miles of driving for every hour of charging. A wider variety of 240-volt chargers are coming on the market that charge at different speeds, with charge times that vary depending on the car and charger. Some systems, such as Tesla's High Power Wall Connector home charger, replenish the battery much quicker. DC fast chargers, which can power up to 80 percent of the battery's range range in about 20 to 30 minutes, are expanding around the country, but they're still few and far between. There are only about 300 DC fast chargers publically available. In addition, Tesla's supercharger network boasts over 500 stations around the country, and those powerful chargers can restore 100 miles of range in as little as 20 minutes for the Tesla Model S.

Can electric vehicles cause a power blackout?
Theoretically, yes, if enough of them were charged during peak times in one local area. We're a long way from that in terms of electric-car penetration, and smart grid technology is improving management of the grid. Plus, the risk is mitigated by the fact that most people will prefer to do most of their charging at night, when demand on the power grid is much lower. According to calculations by the U.S. Department of Energy's Pacific Northwest National Labs, the country has enough excess capacity to charge at least 150 million electric cars at off-peak times, without building a single additional power plant. Many utilities are committed to building more charging infrastructure to meet the demand from electric cars, which they see as expanding their market and possibly providing grid storage through the electric vehicle batteries.


What is the Future of Solar Power in the United States?

US Solar Market Grows 95% in 2016, Smashes Records

In its biggest year to date, the United States solar market nearly doubled its annual record, topping out at 14,626 megawatts of solar PV installed in 2016. This represents a 95 percent increase over the previous record of 7,493 megawatts installed in 2015. GTM Research and the Solar Energy Industries Association (SEIA) previewed this data in advance of their upcoming U.S. Solar Market Insight report, set to be released on March 9, 2017.

For the first time ever, U.S. solar ranked as the No. 1 source of new electric generating capacity additions on an annual basis. In total, solar accounted for 39 percent of new capacity additions across all fuel types in 2016. "What these numbers tell you is that the solar industry is a force to be reckoned with," said Abigail Ross Hopper, SEIA's president and CEO. "Solar's economically winning hand is generating strong growth across all market segments nationwide, leading to more than 260,000 Americans now employed in solar."

Success this year was driven largely by the utility-scale segment, which was bolstered by a pipeline of projects initially hedging against the extension of the federal Investment Tax Credit. Not only did it represent the most megawatts installed, but the utility-scale segment also featured the highest growth rate of any segment, growing 145 percent from 2015. "In a banner year for U.S. solar, a record 22 states each added more than 100 megawatts," said Cory Honeyman, GTM Research's associate director of U.S. solar. "While U.S. solar grew across all segments, what stands out is the double-digit-gigawatt boom in utility-scale solar, primarily due to solar's cost-competitiveness with natural-gas alternatives."

The non-residential market also exceeded expectations, with two major growth drivers in the segment. The first is community solar, adding a record total of more than 200 megawatts, led by Minnesota and Massachusetts. Second, rate design and net energy metering fueled a rush in project development and installation growth across several major state markets, most notably in California.

For the first time since 2011, non-residential installation growth surpassed residential solar growth, which posted a still-impressive 2,583 megawatts. While growth in California's residential market has begun to level out, strong growth in markets like Maryland, New Jersey and a handful of emerging states where solar has achieved grid parity, helped the residential segment to grow 19 percent year-over-year. As a result of a remarkable 2016, the U.S. is now home to more than 1.3 million solar PV installations, with a cumulative capacity of over 40 gigawatts.