Tag: Energy Efficiency

‘Everything You Need to Know About the Wild World of Heat Pumps’

That’s the title of an article in a February 14th post from MIT — https://www.technologyreview.com/2023/02/14/1068582/

I have written about and provided my own explanations regarding how heat pumps differ from forced air furnaces and traditional A/C systems, but the article cited above goes the extra mile.

If you’ve spent a night in a hotel or motel, you have probably slept in a room that was heated or cooled by a heat pump, because invariably that’s what those units are which you saw and controlled under each window.

In my other post today, heat pumps provide the heating and cooling for every Boxabl home. They are also what heats and cools many electric vehicles, since they require less battery power than conventional electric car heaters.

I was surprised to hear that heat pumps were invented in the 1850s but only started being used to heat and cool homes in the 1960s. It took the global climate crisis and the need to reduce our dependence on fossil fuels to make them the hottest trend in new homes.

Speaking of new homes, however, I lamented as recently as last fall that I haven’t found a single new Denver area home builder which has abandoned gas-based home heating or even offers an upgrade to heat pumps. If you know of one, please tell me, because I’d be happy to promote that home builder in a future column.

The MIT article provides some useful information, including about the rebates being offered for heat pump installations. It also debunks the myth promoted by fossil fuel interests that heat pumps don’t work in colder climates. They are actually in use from Alaska to Maine, where, for example, my sister in Kingfield, Maine, installed a heat pump in her home to save on her fuel oil bill. Her fuel oil vendor told her that the adoption of heat pumps by her neighbors has noticeably reduced his sale of fuel oil in that rural community near the Canadian border.

According to the article, 60% of the homes in Norway are heated by heat pumps, as are 40% of the homes in Finland and Sweden (where another of my sisters lives).

“Wherever you look,” the MIT article concludes, “the era of the heat pump has officially begun.”

John Avenson of Westminster Is a Committed Teacher of Energy Efficiency

The sponsors of the annual Metro Denver Green Homes Tour, held on the first Saturday each October, are preparing to “go virtual” in case an  in-person tour is not allowed.

John Avenson’s house at 9988 Hoyt Place, Westminster

That will be accomplished by creating online video tours of the most notable “green” homes featured over the past 20 years. Since I’m on the steering committee for the tour and have the equipment and experience from creating video tours of homes for sale, I volunteered to create those video tours, starting with John Avenson’s home at 9988 Hoyt Place in Westminster.

By clicking here, you can view the 41-minute video tour, led by John, which I created last Friday. It is highly educational.

John Avenson

Many people, myself included, have created homes which can be considered a “model” of sustainability, solar power, and energy efficiency, but John is surely the only homeowner who has turned his home into a classroom for teaching it. He even posted pictures and diagrams throughout the house with instructional content about this or that feature, as you will see on that video.

He also hosts monthly Passive House meetings in his home theater which are also streamed online. They can be found at www.meetup.com/Passive-House-Meetup-S-W-Region/

John’s house was originally built by the Solar Energy Research Institute (SERI, now the National Renewable Energy Laboratory or NREL) in 1981 using then-state of the art technology, but John has diligently, and at great personal expense, kept retrofitting his home with newer technology, which he is happy to explain to visitors and which he explains on the 41-minute video.

CERV monitor screenshot

For example, because of increased insulation and Alpen quadruple-paned windows, he was able to get rid of SERI’s supplemental natural gas furnace, installing a conditioning energy recovery ventilator (CERV) which is powered electrically. His grid-tied solar PV system provides all his home’s energy needs and has reduced his Xcel Energy bill to under $10 per month — the cost of being connected to the electrical grid.

Some of the technological innovations featured in my video with John were new to me. For example, the Alpen windows across from his kitchen have horizontal micro-etching which redirects the sun’s rays 90° upward to his ceiling instead of straight through the glass, reducing the need for lighting.

John provided his email address in the video, saying that his “learning center” is open 24/7 and that he welcomes all inquiries and visitors.