Archive for the ‘renewable energy’ Category

People who live near wind turbines prefer them to solar and fossil plants

March 19th, 2019
Wind turbines near Palm Springs, Calif.

Enlarge / Wind turbines near Palm Springs, Calif. (credit: nate2b / Flickr)

More and more people are finding themselves with a new neighbor: a commercial electricity-generating system. As electricity grids move from centralized fossil fuel plants to decentralized renewables, the world is switching from fewer, larger plants to more, smaller ones. For some people, this means they're looking out of their windows at wind turbines that weren't there a few years ago.

How do people feel about these turbines? That may seem like a question best answered with "why should we care?" but if we get serious about addressing climate change, lots of people might end up living with generating hardware. To better understand people's preferences, researchers Jeremy Firestone and Hannah Kirk analyzed the results of a large-scale survey on attitudes toward wind turbines. The results, published this week in Nature Energy, show that people in both red and blue states who live near wind turbines would rather keep them than swap them out for either solar or fossil fuel plants.

Wind over coal

The results came from a survey of 1,705 people living less than five miles from at least one commercial-scale wind turbine across the United States. The survey, conducted in 2016 by the US Department of Energy's Lawrence Berkeley National Laboratory, included a hefty set of questions aiming to get a full understanding of how community members feel about their local turbines. It asked questions like how involved people felt in the planning process for the project, how noticeable the turbines are from people's homes, and whether they notice the impact of things like turbine noise.

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Posted in Behavioral science, renewable energy, science, wind energy | Comments (0)

New Mexico the most coal-heavy state to pledge 100% carbon-free energy by 2045

March 13th, 2019
Blue sky over solar panels.

Enlarge / University of New Mexico Taos Campus solar photovoltaic array. (credit: Getty Images)

On Tuesday, New Mexico's state House of Representatives passed the "Energy Transition Act," which commits the state to getting 100 percent of its energy from carbon-free sources by 2045. The act passed the state Senate last week. Now the bill awaits the signature of New Mexico's Governor, Michelle Lujan Grisham.

Governor Grisham's office told GreenTechMedia on Tuesday that she would "sign the bill as quickly as possible."

The bill includes interim goals mandating that 50 percent of the state's energy mix be renewable by 2030 and 80 percent of the energy mix be renewable by 2040. The state currently buys no nuclear power, which is not renewable but qualifies as a zero-carbon energy source. The bill passed yesterday does not require that 100 percent of the state's energy be renewable by 2045; it just specifies that no electricity come from a carbon-emitting source.

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Posted in New Mexico, Policy, renewable energy, science, zero-carbon energy | Comments (0)

Renewable energy policies actually work

February 26th, 2019
Image of solar panels.

Enlarge (credit: Lawrence Berkeley Lab)

For most of the industrial era, a nation's carbon emissions moved in lock step with its economy. Growth meant higher emissions. But over the past decade or so, that's changed. Even as the global economy continued to grow, carbon emissions remained flat or dropped a bit.

It would be simple to ascribe this to the explosion in renewable energy, but reality is rarely so simple. Countries like China saw explosive growth in both renewables and fossil-fuel use; Germany and Japan expanded renewables even as they slashed nuclear power; and in the United States, the federal government has been MIA, leading to a chaotic mix of state and local efforts. So it's worth taking a careful look into what exactly might be causing the drop in emissions.

That's precisely what an international group of researchers has now done, analyzing what's gone on in 79 countries, including some that have dropped emissions, and others that have not. The researchers find that renewable energy use is a big factor but so is reduced energy use overall. And, for both of these factors, government policy appears to play a large role.

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Posted in Energy, Policy, renewable energy, science | Comments (0)

Startup will store energy by forcing compressed air in a defunct zinc mine

February 14th, 2019

An energy storage startup called Hydrostor is planning to build an Advanced Compressed Air Energy Storage (A-CAES) project in Australia, using an out-of-operation underground zinc mine as a container for the compressed air.

Hydrostor announced its plans this week after being awarded AUD $9 million (USD $6.4 million) in grants from Australian government institutions.

Compressed air energy storage (CAES) is a sort of physical battery (as opposed to a chemical battery) that uses excess electricity to compress air. The compressed air is stored in a tank, in a balloon, or in an underground cavern. When more electricity is needed, the compressed air is heated, which drives a turbine as it expands.

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Posted in Biz & IT, Compressed air storage, Energy, mining, renewable energy, science | Comments (0)

When will electric airliners make sense?

December 14th, 2018
Image of an electric aircraft with many small motors.

Enlarge (credit: NASA)

Currently, the world is struggling to keep its carbon emissions from rising. But to reach the longer-term goals we have for stabilizing the climate, we're going to have to do far more than roll out some renewable energy. Keeping the earth from warming by 2°C above preindustrial temperatures means a deep decarbonization of our energy use. Which means that we not only have to go fully carbon neutral in generating electricity, but we have to start using those emissions-free electrons to handle our heating and transportation needs.

For things like cars and busses, that process has already started. But there's one weight-sensitive mode of transportation where batteries may not be able to bail us out: air travel. The relatively low energy density of batteries means that you need a lot of them—plus the weight and space they take up—to power an aircraft. For this reason, many people have decided that we'll need biofuels to power air travel. Yet there are companies that are planning on developing electric passenger aircraft.

So who's being realistic? To find out, an international team has done an evaluation of whether battery-powered electric aircraft can become viable and when it's possible they'll reach the market.

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Posted in batteries, electric aircraft, Energy, renewable energy, science | Comments (0)

New material could up efficiency of concentrated solar power

October 19th, 2018
New material could up efficiency of concentrated solar power

Enlarge (credit: OPIC)

With the price of photovoltaics having plunged dramatically, solar is likely to become a major contributor to the electrical generating mix in many countries. But the intermittent nature of photovoltaics could put a limit on how much they contribute to future grids or force us to develop massive storage capabilities.

But photovoltaics aren't the only solar technology out there. Concentrated solar power uses mirrors to focus the Sun's light, providing heat that can be used to drive turbines. Advances in heat storage mean that the technology can now generate power around the clock, essentially integrating storage into the process of producing energy. Unfortunately, the price of concentrated solar hasn't budged much, and photovoltaics have left it in the dust. But some materials scientists may have figured out a way to boost concentrated solar's efficiency considerably, clawing back some of photovoltaics' advantage.

Feel the heat

Solar thermal revolves around transfers of heat. Sunlight is used to heat up a working fluid at the mirrors' focus. That then transfers the heat either to a storage system or directly to another fluid that is used to drive a turbine—typically steam. Higher temperatures typically mean more work can be extracted, making the efficiency of these transfers critical.

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Posted in concentrated solar, materials science, renewable energy, science, Solar energy | Comments (0)

Health benefits of wind and solar offset all subsidies

August 17th, 2017

Enlarge

Wind and solar energy are obviously essential in reducing carbon emissions, but they also have a remarkable side effect: saving lives. As they edge out fossil fuels, renewables are reducing not just carbon emissions, but also other air pollutants. And the result is an improvement in air quality, with a corresponding drop in premature deaths.

A paper in Nature Energy this week dives into the weeds by trying to estimate the economic benefits of wind and solar power across the whole of the US. Berkeley environmental engineer Dev Millstein and his colleagues estimate that between 3,000 and 12,700 premature deaths have been averted because of air quality benefits over the last decade or so, creating a total economic benefit between $30 billion and $113 billion. The benefits from wind work out to be more than 7¢ per kilowatt-hour, which is more than unsubsidized wind energy generally costs.

Death is in the air

Poor air quality is a tricky beast in public health, since it’s not obvious when someone dies as a result of air pollution. The World Health Organization estimates that air pollution leads to around 7 million premature deaths globally each year—people dying earlier than they otherwise would have from heightened incidence of cancer, heart disease, and respiratory disease.

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Posted in climate change, public health, renewable energy, science | Comments (0)

Health benefits of wind and solar offset all subsidies

August 17th, 2017

Enlarge

Wind and solar energy are obviously essential in reducing carbon emissions, but they also have a remarkable side effect: saving lives. As they edge out fossil fuels, renewables are reducing not just carbon emissions, but also other air pollutants. And the result is an improvement in air quality, with a corresponding drop in premature deaths.

A paper in Nature Energy this week dives into the weeds by trying to estimate the economic benefits of wind and solar power across the whole of the US. Berkeley environmental engineer Dev Millstein and his colleagues estimate that between 3,000 and 12,700 premature deaths have been averted because of air quality benefits over the last decade or so, creating a total economic benefit between $30 billion and $113 billion. The benefits from wind work out to be more than 7¢ per kilowatt-hour, which is more than unsubsidized wind energy generally costs.

Death is in the air

Poor air quality is a tricky beast in public health, since it’s not obvious when someone dies as a result of air pollution. The World Health Organization estimates that air pollution leads to around 7 million premature deaths globally each year—people dying earlier than they otherwise would have from heightened incidence of cancer, heart disease, and respiratory disease.

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Posted in climate change, public health, renewable energy, science | Comments (0)

Environmental Protection Agency sets new renewable fuel standards for 2016

December 1st, 2015

(credit: Robenalt @ Flickr)

For the first time since 2013, the US Environmental Protection Agency has issued renewable fuel standards for the nation, upping the amount of ethanol in our gasoline supply. In 2016, renewable fuels—mostly corn ethanol—must make up 10.10 percent of the national fuel supply, or 18.1 billion gallons. The EPA also issued final renewable fuel standard for 2014 and 2015, showing that next year’s target is a slight increase over the past two years. In 2014—the last year that the Energy Information Administration has calculated total US gasoline consumption (136.8 billion gallons), the total percentage of renewable fuels was 9.2 percent, or 16.3 billion gallons.

Almost all of this ethanol will make its way into our cars in the form of E10 gasoline, which is a blend of 10 percent ethanol and 90 percent gasoline. E10 is widespread throughout the US, and mandated in a number of states (mainly throughout the midwest). The ethanol acts as an oxygenator and anti-knocking agent for the fuel, replacing the groundwater pollutant MTBE (which itself replaced tetraethyl lead). E10 is slightly less energy dense than “regular” gasoline and so cars’ fuel economy will be three to four percent lower when using the fuel. This is offset by slight decreases in CO emissions (as well as the intended reduction in greenhouse gases).

In 2016 the overall percentage of renewable fuels will be just over 10 percent, leading to criticism from the oil industry warning about damage to our cars’ engines and fuel systems. At higher concentrations, ethanol-gasoline blends can be corrosive to some metals and materials used for hoses, gaskets, and seals; generally blends above E10 (E15 and E85) should only be used by “flex-fuel” vehicles that have been designed to tolerate the increased ethanol levels. Neither have much popularity in the US though, being confined mainly to corn-producing states in the midwest.

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Posted in Cars Technica, E=10+, renewable energy | Comments (0)