CU Boulder solar conference showcases latest energy-efficient technology

Aug. 11—An electric motorcycle with a 100-mile range, four-pane glass windows and a remote-controlled water recirculation pump are just a few of the latest energy-efficient technologies that were on display at the University of Colorado Boulder on Friday.

CU Boulder hosted the 52nd annual national American Solar Energy Society solar conference Tuesday through Friday. Friday included an electric vehicle show and workshop with speakers discussing energy efficient technology.

Volunteer Tobias Strohe brought his own electric motorcycle to display, and said it can travel 100 to 120 miles before it needs to be charged. He said it essentially functions like a normal motorcycle without the range issues riders usually face.

Strohe said he likes to ride his motorcycle for a few hours at a time in the canyons near Nederland and still has plenty of charge left by the time he returns home. On a long road trip, he's able to fast-charge in about 40 minutes. By the time the motorcycle needs a charge, he said he's ready to get food or take a break anyway.

For his normal day to day, Strohe takes the motorcycle to work and plugs it in at night when he gets home. It's then ready to go the next day and he never has to take the time to visit a gas station.

Outside of the electric vehicle show, speakers at the conference discussed many of the latest technologies available for home installation. John Avenson, owner of Sustainable Architecture LLC, gave a demonstration on the latest energy efficiency technology for homes. One sample he showed was of a four-pane window, which helps prevent heat from escaping a home.

"This glass is better than a two-by-four wall with insulation," he said.

Avenson also showed a hot water recirculation pump that conserves and delivers hot water quickly to the sink or shower. Avenson said he has one in his home that cost about $400 and is operable by using a remote.

He also suggested some best practices for making a home more energy efficient. He said getting an energy audit is a good start to find out how much air comes in and out of the home per hour. Ensuring a home's insulation is multiple inches thick is also important, he said.

An air particle detector and a CERV fresh air machine, which can measure air quality in home and determine when ventilation is needed, are also good investments, Avenson said. Using those tools, he said, is a great way to begin learning about air quality levels within the home.

Bill Lucas is a co-founder of GB3 Energy and heat pump installer. He discussed the advantages of heat pumps, which are a more environmentally-friendly way to heat a home.

Lucas said heat pumps work well, and even if people are nervous about installing them, they can include a backup system which will still decarbonize the load by 70% to 80%. He explained heat pumps work like refrigerators and take cool air and convert it to warm air, making heat and not creating it.

"It is doable, and it's not more expensive," Lucas said. In 2022, he said heat pumps even surpassed furnaces in installation numbers.

Lucas said traditional heaters and air conditioners also contain refrigerants, which are highly toxic to the environment. One pound of refrigerant, if released into the environment, is equivalent to one ton of carbon. Refrigerant management is listed at fifth on a Project Drawdown list of top ways to reduce carbon emission.

"They are so toxic to the environment we really need to think about how to manage them," Lucas said.

Sean Cunningham of Resolution Energy has been an installation contractor for more than 25 years. He said 20% to 30% of a home's energy goes to water heating, which can be reduced with heat pump water heaters and can result in 81% reduction in greenhouse gases.

"There's phenomenal potential with heat pump water heaters," Cunningham said.

With solar panels installed, there are zero green house emissions. The downside is without solar panels already installed, the costs for a heat pump water heater are "through the roof," Cunningham said. He said an alternative to solar panels is a solar thermal system coupled with small, electric demand heaters as a backup for a more cost-effective option.

The solar panel industry was discussed in depth by National Renewable Energy Laboratory Research Fellow and Chief Scientist Dave Ginley. He said other forms of energy like wind, natural gas, nuclear and coal will either level off or decrease in use in the future, with solar energy taking the lead.

Ginley said silicone solar cells are the future, and they're being made more efficient by making them into tandems, or cells connected in a series.

"You can gain anywhere from 5% to 10% efficiency on a tandem solar cell," Ginley said.

The increase in solar cell efficiency is also why solar energy costs have decreased, which he said is "marvelous." Even so, Ginley said, the United States is nowhere where it needs to be with solar energy to mitigate global warming.

"Even in the U.S. ... and even (in the individual states) where we have commitments to make 100% renewable energy, we're still not making the policy to support it," Ginley said.

For more information on the conference or latest technology, visit