ASK EARTHA: How to Efficiently Cool Your Home
Dear Eartha, Is it just me, or does it feel hotter this summer? Am I crazy for thinking about getting an air conditioner?
As rapper Nelly presaged, “It’s getting hot in here.” And while he definitely wasn’t referring to heat building up in the atmosphere, he was right. It is getting hotter. And not just in Summit County.
This past June was the hottest ever recorded in North America. In fact, it was two degrees warmer than the average June temperature from 1991 – 2020. Locally, the Dillon weather station recorded six days in a row of record high temperatures. Because of climate change, average temperatures across Colorado are expected to increase by up to five degrees Fahrenheit over the next 30 years, making 80-degree temps a lot more common in our mountain community. That has all sorts of implications, like a shorter ski season and increased fire danger, not to mention more visitors escaping the heat in their own communities.
Compared to the temperatures under the “heat dome” covering the Pacific Northwest, our 80-degree days were balmy. And while the heat has broken here for now, last week another heat wave impacted communities further west of us. Grand Junction hit an all-time high of 107 degrees. Arizona, California, Nevada, Utah and even parts of Oregon and Idaho saw triple-digit days and excessive heat warnings.
During COVID we panic bought toilet paper. Now, folks are rushing out to buy air conditioners. And for good reason – heat exposure is often more deadly than other natural disasters like hurricanes and tornadoes. Given increasing temperatures and wildfire-caused poor air quality leading to shuttered windows, it’s not unreasonable to think you might need air conditioning in the future. But how can you do that responsibly? Well, friends, let me tell you about cold climate heat pumps.
Introducing Cold Climate Heat Pumps
Yes, you read that right – something called a heat pump can be used for cooling. Heat pumps are essentially air conditioners that can be reversed, and because of that, they can both heat and cool. There are different types of heat pumps, and you may have heard of ground-source heat pumps before. What I’ll describe here are air-source heat pumps. If you’ll recall your high school science classes, unless the temperature is absolute zero, there’s still heat in cold air. So in the winter, a heat pump pulls energy from the outdoor air and transfers it (in the form of heat) inside. In the summer, the process is reversed – heat from inside the home is transferred outside. This might seem like magic, but it’s science!
I know there may be folks in our community who are skeptical that heat pumps can adequately warm a home in winter. In the past that was true; heat pumps didn’t work well in really cold temperatures. Now, however, a handful of heat pump manufacturers make cold climate heat pumps which heat efficiently at temperatures well below zero. Our opinions just need to catch up to the technology.
Why am I nerding out over HVAC equipment? Because heat pumps run on electricity, making them an important strategy for decreasing the carbon footprint of our buildings. Energy use in homes and businesses accounts for nearly two-thirds of the carbon pollution in Summit County. While natural gas is increasingly common for heating buildings, it has a significant carbon impact. And renewable natural gas is a marketing myth. So, if we’re going to make a dent in our building emissions, we need to transition to electric space and water heating.
There’s actually a term for this – beneficial electrification. Why “beneficial”? Because electricity is getting cleaner every year. In fact, Xcel Energy has a goal to produce 80 percent renewable electricity by 2030 and 100 percent carbon-free electricity by 2050. The more we can heat – and cool – our homes with electricity, the cleaner our energy use will be.
I realize I’m going on and on about heating when we started talking about air conditioning. Remember that a heat pump can do both. And for those with high cost or highly inefficient heating systems like propane or electric baseboard, a heat pump will provide you with significant cost savings in the winter, in addition to the bonus of air conditioning in the summer. I think that’s pretty cool – pun intended.