Most recent
Trending
Top Videos
The best of EcoWatch, right in your inbox. Sign up for our email newsletter!
The U.S. could reduce greenhouse gas emissions from electricity generation by 78 percent below 1990 levels within 15 years just by using renewable sources such as wind and solar energy, according to a former government research chief.
The nation could do this using only technologies available right now and by introducing a national grid system connected by high voltage direct current (HVDC) that could get the power without loss to those places that needed it most, when they needed it.
This utopian vision—and it has been dreamed at least twice before by researchers in Delaware and in Stanford, California—comes directly from a former chief of research in a U.S. government agency, the National Oceanic and Atmospheric Administration (NOAA).
Dr. Alexander MacDonald, a distinguished meteorologist, was until recently, the head of NOAA’s Earth System Research Laboratory in Boulder, Colorado.
Supply and Demand
He and colleagues at the University of Colorado report in Nature Climate Change that instead of factoring in fossil fuel backup or yet-to-be-invented methods of storing electricity from wind and solar sources, they took a new look at the simple problems of supply and demand in a nation that tends to be sunny and warm in the south and windy in the north, but not always reliably so in either place.
Their reasoning was that storage technologies could only increase the cost of renewable energy and increase the problem of reducing carbon emissions.
So they modeled the U.S. weather on timescales of one hour over divisions of the nation as small as 13 square kilometers to see what costs and demand and carbon dioxide emissions would be and how easily renewable power could meet the demand.
They reasoned that even though wind turbines are vulnerable to periods of calm and that solar energy sources don’t do much in rainy weather or at night, there would always be some parts of the country that could be generating energy from a renewable source.
They then factored in future costs—the cost of both wind and solar has been falling steadily—and scaled up renewable energy to match the available wind and sunlight in the U.S. at any time.
“Our research shows a transition to a reliable, low-carbon, electrical generation and transmission system can be accomplished with commercially available technology and within 15 years,” Dr. MacDonald said.
The model embraced fossil fuel sources as well as renewable ones, for purposes of comparison. It revealed that low cost and low emissions are not mutually exclusive. The U.S. could have both.
“The model relentlessly seeks the lowest-cost energy, whatever constraints are applied,” Christopher Clack, a physicist and mathematician with the Cooperative Institute for Research in Environmental Sciences at the University of Colorado Boulder and a co-author of the study, said. “And it always installs more renewable energy on the grid than exists today.”
Even in a scenario where renewable energy cost more than experts predicted, the model produced a system that cut carbon dioxide emissions 33 percent below 1990 levels by 2030 and delivered electricity at about 8.6 cents per kilowatt hour (kWh). By comparison, electricity cost 9.4 cents per kWh in 2012.
If renewable energy costs were lower and natural gas costs higher, as is expected in the future, the modeled system sliced carbon dioxide emissions by 78 percent from 1990 levels and delivered electricity at 10 cents per kWh. The year 1990 is the baseline for greenhouse gas calculations.
Low-Cost Sources
The model achieved its outcome without relying on any new electrical storage systems. The national grid did need augmentation from nuclear energy, hydropower and natural gas, but the real innovation would be the connection of large numbers of low-cost renewable energy sources to high-energy-demand centers, using efficient new transmission systems.
It seems that HVDC transmission is the key to keeping costs down and Dr. MacDonald compared such power links to the interstate highways that cross the U.S. and which transformed the U.S. economy 50 years ago.
“With an ‘interstate for electrons,’ renewable energy could be delivered anywhere in the country while emissions plummet,” he said.
“An HVDC grid would create a national electricity market in which all types of generation, including low-carbon sources, compete on a cost basis. The surprise was how dominant wind and solar could be.”
YOU MIGHT ALSO LIKE
Elon Musk vs. Warren Buffett: The Billionaire Battle Over the Future of Solar Power
Copenhagen Set to Divest Funds Out of Coal, Oil and Gas Holdings
Trending
Trending
Farms with just one or a handful of different crops encourage fewer species of pollinating and pest-controlling insects to linger, ultimately winnowing away crop yields, according to a new study.
Up to half of the detrimental impacts of the "landscape simplification" that monocropping entails come as a result of a diminished mix of ecosystem service-providing insects, a team of scientists reported Oct. 16 in the journal Science Advances.
Monocrop palm oil plantation Honduras.
SHARE Foundation / Flickr / CC BY-NC 2.0
"Our study shows that biodiversity is essential to ensure the provision of ecosystem services and to maintain a high and stable agricultural production," Matteo Dainese, the study's lead author and a biologist at Eurac Research in Bolzano, Italy, said in a statement.
It stands to reason that, with declines in the sheer numbers of insects that ferry pollen from plant to plant and keep crop-eating pests under control, these services will wane as well. But until now, it hasn't been clear how monocultures affect the number and mix of these species or how crop yields might change as a result.
Aiming to solve these questions, Dainese and his colleagues pulled together data from 89 studies cutting across a variety of landscapes, from the tropics of Asia and Africa to the higher latitudes of northern Europe. They tabulated the number of pollinating and pest-controlling insects at these sites — both the absolute number of individuals and the number of species — along with an assessment of the ecosystem services the insects provided.
In almost all of the studies they looked at, the team found that a more diverse pool of these species translated into more pollination and greater pest control. They also showed that simplified landscapes supported fewer species of service-providing insects, which ultimately led to lower crop yields.
The researchers also looked at a third measure of the makeup of insect populations — what they called "evenness." In natural ecosystems, a handful of dominant species with many more individuals typically live alongside a higher number of rarer species. The team found as landscapes became less diverse, dominant species numbers dwindled and rare species gained ground. This resulting, more equitable mix led to less pollination (though it didn't end up affecting pest control).
"Our study provides strong empirical support for the potential benefits of new pathways to sustainable agriculture that aim to reconcile the protection of biodiversity and the production of food for increasing human populations," Ingolf Steffan-Dewenter, one of the study's authors and an animal ecologist at the University of Würzburg in Germany, said in the statement.
The scientists figure that the richness of pollinator species explains around a third of the harmful impacts of less diverse landscapes, while the richness of pest-controlling species accounts for about half of the same measure. In their view, the results of their research point to the need to protect biodiversity on and around crops in an uncertain future.
"Under future conditions with ongoing global change and more frequent extreme climate events, the value of farmland biodiversity ensuring resilience against environmental disturbances will become even more important," Steffan-Dewenter said.
Reposted with permission from our media associate Mongabay.