UNH researchers seek regional, renewable solutions

In the state-of-the-art Chase Ocean Engineering Laboratory on the University of New Hampshire’s Durham campus, students and researchers test their designs in huge tanks of water with simulated waves and currents.

They are mindful of all the ways an experiment could go wrong, because outside, they don’t have that kind of control.

A team of engineering students and professors recently tested a tide turbine in the Great Bay estuary. They moored off the old General Sullivan Bridge between Newington and Dover, led by Martin Wosnik, an assistant professor of mechanical engineering.

Wosnik said the turbine had to be lowered from a 35-foot floating platform in just the right place and time. There’s a limited area, between the water’s width and depth, where the current is fast enough to properly spin the turbine while remaining outside of the lane of marine travel. There were only about 10 minutes to catch the slack water from the incoming tide.

If something were to go wrong, it would happen “quickly and badly,” Wosnik said. But professor Ken Baldwin, director of the Center for Ocean Engineering, who watched from the bridge above, said it looked as though nothing at all was happening.

“It may not look treacherous from shore, but it’s quite dangerous,” said Wosnik. He said the platform was struck by an “iceberg” during the February test (really just a floating layer of ice) and one of the crew members was humming the theme song from the “Titanic” movie.

Still, the test was a success, producing energy as anticipated. “That’s the conclusion. It works,” said Baldwin. Another test with an improved version is planned for early April, this time actually using the energy that is made.     

Researchers at the University of New Hampshire are involved in several projects to develop renewable energy on a regional level, finding small solutions that could work together to help solve the energy crisis. The school is working on new technology, like water power, but also wind and solar power, and better biofuels. Meanwhile, the university’s campus runs partly on alternative energy from landfill gases.

Hydrokinetic energy comes from the natural flow of waterways moving at a pace of more than a couple of knots. “The benefit is it can harness energy that’s there anyway,” said Wosnik. 

The tide turbine works similar to a wind turbine, but, because of the density of water, it doesn’t have to spin as fast. The turbine UNH tested doesn’t look like a wind mill, but is helix shaped with each blade like a bent airplane wing, so it’s always making contact with the water flow.  

The energy output is not as high as with fossil fuels, but it is a clean, renewable energy source. Still, there are potential environmental consequences that have to be averted. If the amount of energy extracted from the water flow is too high, it could disrupt the fish habitat, Baldwin said.

Though there are concerns about birds flying into wind turbines, Wosnik said studies with fish have shown that they can sense solids from pressure and can navigate around slow-moving turbines. He said that makes injuries to fish only a minor concern.

The University of New Hampshire aims to be a testing facility for water turbines, not to manufacture or sell them, said Baldwin. Using the natural resources and expansive infrastructure available to the school, they hope to offer advice for the companies that do manufacture the turbines.

While the Seacoast is ideal for testing hydrokinetic energy, the area could not produce it in a significant way. There are few places in the United States where this type of energy would be feasible, and Alaska may be best for it, Wosnik said.

The next step is to work with larger scale models, but the project lacks funds. The researchers are seeking federal grant funding for alternative energy development, and Baldwin is hopeful the new presidential administration will provide it.  

“If you have an idea, you start very small,” said Wosnik. He said you have to make sure each model works before making a larger one.

The ocean engineering department is also working on wave energy and hopes to test a model outdoors this summer, but Baldwin said that technology is not as far along as tide turbines.

Hydrokinetic energy alone is not going to solve the energy crisis. But, Wosnik said, “This technology is ready to become a part of the energy mix, if properly developed.”

Kevan Carpenter, project director of the Climate Change Research Center, said it’s going to take a diverse array of solutions to solve the energy problem. He said each solution will be a result of the resources within a particular region.

The center has an observation tower in a former wartime building on Appledore Island, one of the largest of the Isles of Shoals. It’s part of a network of observatories in a project called AIRMAP, in which researchers study the changing climate and air quality. Carpenter said New England is like the nation’s “tailpipe” because of air masses that push emissions this way. He is currently studying the phases and sources of mercury.

Prior to last year, the center was run off generators in the summer and closed during the winter. Carpenter said they were missing the big picture without year-round data. He said sustainable energy was appropriate for their mission, and they now use a hybrid system of wind and solar power.

The island is an ideal place for wind power, where speeds offshore are fast during the winter, and for solar power during the sunnier months. He said fall and spring are the most likely times for a power outage, but even then, a battery would run for 36 hours.

Records of wind speeds helped determine what kind of wind turbine to use and what to expect from it. They chose a 7.5-kilowatt wind turbine and 4.4-kilowatt solar panels, he said. It’s not enough to run the entire island, but Carpenter said other residents are being inspired to become more energy efficient.

The center now provides other UNH students with educational opportunities about renewable energy. Carpenter said there are plans to monitor the energy output more thoroughly this summer. It will be the first time the system will run up to capacity.

Because Appledore Island is a nesting location for migrating birds and a banding station for the Audubon Society, some people worried that the wind turbine would kill birds. Thousands of birds fly through the area, Carpenter said. This meant a lengthy conception time and permit process of about 4 years.

The result is an 80-foot wind turbine that can be lowered down at the flip of a switch. Also, one of the wind mill blades is painted black so that it is easier to see when spinning. Over the past two summers, not a single dead bird was found near the turbine. “This size and style is not impacting birds,” Capenter said.

There have also been no maintenance problems, he said. “That’s something communities are going to want,” he said, “They’re going to want a reliable power source that’s low maintenance.”

In addition to water, wind and solar power, UNH is researching sustainable fuels. Ihab Farag, a chemical engineering professor who is part of the UNH Biodiesel Group, said the future is not in vegetable oils, but algae.

He said collecting used cooking oils from restaurants won’t be enough to replace fossil fuels, and there are problems with growing vegetable oils for biofuels, too. There isn’t enough land to grow corn or soybeans to meet the demand of 60 billion gallons per year. Some farmers have been switching their traditional food crops with crops for fuel, meaning less food for people and animals. This is also driving food prices up.

It’s becoming an ethical issue, Farag said. “Do we use the land to make food or do we use the land to make energy?”

He said the amount of corn it takes to make 20 gallons of biofuel could feed a person for a year. Also, he said, growing that corn requires 1,500 gallons of water, while the same amount of algae can grow with just five gallons. The consequences of using food and water for fuel are felt largely in poorer countries, though they use less fuel than the United States.

Farag said researchers have to look for other sources of biofuel, and that’s where micro algae comes in. These single-cell plants make oil during photosynthesis, which can be extracted. It grows fast, some doubling in a day, and can usually be harvested in a week as opposed to six to nine months for most crops.

The equivalent to an acre of algae can make more than 100 times the biofuel that soybeans can, and algae doesn’t need fertile land. It can grow in a factory or near one, where it would take in some of the carbon dioxide that is emitted if fossil fuels are used there, he said.

Still, there are technical challenges ahead for growing and harvesting algae, including finding the best type and the best way to convert it, Farag said. But he said it could be commercialized in two or three years with the funds to continue research.  

Will Kessler graduated from UNH last year after studying natural resources. He’s now a solar specialist managing the New Hampshire office of Revision Energy, which is based in Maine, installing solar power and hot water, and wood pellet boilers. He said he wanted to move beyond academia and policy and put alternative energy into practical use.
“We should be using less fossil fuels and more of own creativity,” he said. 

In 2006, UNH updated its own source of energy with a new cogeneration plant on the Durham Campus. It retains waste heat normally lost during the production of electricity and instead uses this energy to heat buildings, in turn reducing harmful emissions.

This year, UNH also became the first university in the United States to use landfill gas as its primary energy source. ECOLine pipes enriched and purified gas from Waste Management’s landfill in Rochester to the campus. Excess energy from the project will be sold as renewable energy certificates to help finance the capital costs of the project and to invest in additional energy efficiency projects on campus. The project is part of UNH’s long-term climate action plan, called WildCAP, which has an ultimate goal of zero emissions.