Source: dailyprogress.com
A bag of shredded hemp on the way to being turned into pulp and
used for paper and other products sits on a table, at Pure Vision
Technology, a biomass factory in Ft. Lupton, Colo.
William McNamara learned about the problem with petroleum in college. Not a problem with the substance itself, but the fact there’s a limited amount of it here on the planet. And so he started thinking and planning, looking for different ways of generating energy that could help people move away from fossil fuels.
“Petroleum is really important to us,” McNamara said. “We see it as powering our cars and heating our homes, but in reality, a lot of the chemical precursors we use for plastics and drugs come from petroleum, so if we’re just burning this stuff for fuel, we’re losing a resource we need to sustain modern life.”
And so McNamara set out to develop an alternative. In the field of alternative energy, a lot of attention is put on solar and wind, but there are other options being explored as well, many of which are still in the planning process in university labs across Virginia. Prof. McNamara and his students in the chemistry department at the College of William and Mary are focusing on a way to mimic how plants operate and create energy through artificial photosynthesis.
“When you look at plants, they’re not taking sunlight and storing electricity in batteries, they harvest it and convert it into a fuel,” McNamara said. “It’s a really efficient way of getting the energy they need. So we’re working to copy that, to generate a chemical fuel we can either burn or combine to create electricity.”
The idea is to move past some of the limitations solar energy has. If someone is using solar energy, if there’s no sunlight, no energy is being harvested or stored in the batteries. That means people have to fall back on traditional ways of powering their homes. The same goes for when it’s dark outside. A home operating on solar power would be running on batteries at night and limited to what could be done. Plants don’t have that problem however. They generate enough fuel during the day to constantly feed off of. To replicate that in theory, all you need is some sun, some water and a little iron.
McNamara’s process runs some solar power through water, using another item, in this case iron molecules, to help reduce protons to hydrogen gas. Once perfected, the idea would be to generate hydrogen gas to burn, while also producing clean water.
“There’s no CO2 here, there’s no hydrocarbon, so you’re not contributing to greenhouse gases,” McNamara said. “If you can split the water into oxygen gas and hydrogen gas, then you can burn that hydrogen and it’s going to release energy. It also would help purify water. If you take sea water and put a catalyst in there, say iron, when you burn the hydrogen, now you’re also generating clean water for people.”
While the process is already understood, it’s the question of how to do it the professor finds himself still working on. In order to create a working energy alternative, it has to be affordable, for either companies or people to buy. Right now, the process to generate artificial photosynthesis is too expensive.
“No one’s going to buy something that costs $500,000 to use in your home,” McNamara said. “If we’re making this claim that we’re going to be renewable, we have to use materials that are affordable. That’s why we’re using iron, we’re focusing on earth abundant metals.”
McNamara and his team test the metals using molecules called ligands. They bind to the metal by sharing electrons and then allow the researchers to change the rate of the reaction. They’re looking for a combination that will work within a model easier and cheaper to produce, a reaction able to be performed over and over in a device, creating hydrogen gas for years without needing to be replaced. Once it’s perfected, a device like this would also help facilities like a space station be able to generate their own energy, rather than relying on supplies from Earth. But as to a timetable? That’s a tougher question.
“I think its feasible technology like this will be viable within 10 to 20 years,” McNamara said. “It takes a lot of time to discover things and invent them, that’s why it’s important to get going on this now, rather than wait for our resources to run out.”
Building with biomass
Plants also play a part in another exploratory project, this one operated by an alum from UVa’s Darden School of Business. Matthew Markee runs the Richmond-based firm Recast Energy, which takes biomas, basically organic matter from plants and animals and even wood in some cases, then transforms it into fuel. The group has worked with companies in Mississippi and Kentucky not just to generate energy, but to help transition from fossil fuels to steam.
“We currently own and operate two biomass facilities that provide steam to industrial facilities,” Markee said. “We have worked on development and acquisitions of industrial steam and standalone biomass power projects across the U.S. and internationally.”
In Mississippi, the firm helped a local group make the switch to a 52,000 lb. per hour steam capacity system, cutting down on their carbon footprint. In Kentucky, they took over a coal-fired boilerhouse in 2010 and by 2012, had it running on biomass, producing 250,000 lb. per hour of steam.
“It makes sense in geographies with abundant wood supply, particularly when it is being harvested sustainably for paper or other industries,” Markee said. The company then can pick up the materials left behind and use it to generate fuel. The company’s operation in Louisville has generated enough interest so that when tree limbs or entire trees fall in city parks, that wood “waste” now is sold and turned into energy. Previously, they had been hauled to the area’s landfills, taking up space.
It’s easier to put together a biomass facility in some ways because there will always be materials left behind. Markee’s company is also exploring the ideas of generating energy from landfill gases, where the materials in the area are used to produce methane.
These facilities don’t come without a cost, however. The Mississippi project was supported by tax-exempt bonds from the Mississippi Bond Finance Corporation and carbon credits.
“Biomass plants have to overcome spreading fixed costs across a smaller output relative to natural gas or coal-fired plants,” Markee explained. For example, a biomass plant can generate a maximum of 50 to 100 megawatts. Natural gas and coal-fired plants can produce several hundred megawatts each.
One key benefit for biomass operations is the fact that a conversion to using them counts toward a company or industry’s compliance with the Clean Power Plan. Some officials are challenging that however, arguing that using a biomass plant could lead to people chopping down usable trees and damaging Virginia’s forests.
In a letter to the Environmental Protection Agency, Donald Beyer, representative for Virginia’s 8th district in the U.S. House, called for the removal of biomass plants from the Clean Power Plan.
“In my state of Virginia, local environmental organizations are concerned that if EPA treats biomass combustion as carbon neutral under the final plan, it will encourage Dominion Virginia Power to burn wood from forests to help meet its emission reduction obligations,” Beyer wrote. “Dominion has already converted three of its existing coal plants to run on biomass fuel and has a hybrid energy center that can burn up to 20 percent biomass for fuel. I share the concern of these local groups that Virginia will become known as a state that harvests forests to reduce its dependence on coal, rather than one that develops renewable technologies that clearly reduce emissions, such as solar and wind.”
Going green
For UVa’s Darden School of Business, saving energy was as simple as pulling out plugs and turning off lights. Yet eight years later, the results are clear. Between 2007 and 2015, the department reduced its carbon footprint by 20 percent and cut the waste headed to the landfill by 64 percent. While other operations research new ways of producing energy, Erika Herz, the department’s director of intellectual capital, said they’ve found simple things also work.
“You just try to push down your use as much as possible,” Herz said. “The more you can drive it down, the less need you have then when you go for a renewable energy project. When you look at what kind of solar project you can do for your money, you want to spend as little as possible and you want to have worked all the kinks out of the system before you start looking. You don’t want to be paying for electricity you didn’t need in the first place.”
Those steps included setting room temperatures to specific points for heating and cooling, as well as turning off lights when someone leaves the room. Another key for the department has been to replace all of the lights with energy efficient versions.
“There’s a lot more efficient lighting than there was 10 years ago,” Herz said. She gives the example of the department’s garage, which stretches for several floors. That helped cut down on the building’s carbon footprint.
Also, the department started focusing on composting organic materials and recycling, rather than sending everything to the landfill. A local company, Black Bear Composting, started collecting food waste from the facility.
“We serve a lot of coffee here, so one of the main things we were able to do is divert all of those coffee grounds, all of the peels from fruit,” Herz said.
The big challenge in all this, she added, was to get people to change the way they did things. That includes making sure lights are turned off when they leave the room and reporting where they see lights have been left on at night, in order to cut down on usage.
The department is looking at projects using solar power, but Herz said there just isn’t a good fit yet. More than some, the department has to find a project that works financially, with the right amount of return.
“It’s getting easier, but electricity is very cheap here,” Herz said. “It’s still very challenging to find projects that have the right return.”
In addition, the way the Darden School of Business is structured, only 10 percent of their electricity need could be helped by solar power. The reason comes from the fact it would be hard to place panels on the grounds and so that leaves only the space on the department’s roof.
“We’re not there yet, but we’ve definitely be investigating,” Herz said.
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