Heat pumps could be key to fighting climate change, but how? We answer your burning questions
There are many reasons why heat pumps are slow to take off in the country, including high costs, a lack of consumer trust, ignorance of the technology at many heating contractors, and a failure of the state’s Mass Save energy efficiency program to embrace full electrification in the home.
As our inboxes confirm – you, the readers, have questions. Many of them. Here are the ones we’ve heard most of the time.
How does a heat pump work?
Heat pumps are electrically operated devices that can transport thermal energy from a cooler to a warmer room. Even when it’s cold outside, the air contains energy. The heat pump draws in this energy and uses it to warm a cool house in winter or to cool it in summer.
One easy way is to imagine a highly efficient and quiet air conditioner that can work both ways.
There are several types of heat pumps, including air source heat pumps that move energy from a device outside a building to a device inside, or a geothermal heat pump (or geothermal heat pump) that draws energy from the ground or groundwater and draws it into a building.
But one thing is clear: this is not the same as the inefficient electrical resistance heating of the mid-1900s.
If we switch to electrifying our homes, but the power grid continues to be powered by oil and gas-fired power plants, won’t we still be contributing to the emissions?
Yes, but less than usual.
On the one hand, heat pumps are very efficient, which means that your overall energy requirement is lower.
On the other hand, as long as electricity is still being generated from fossil fuel-fired power plants, we have a major emissions problem in hand. Because of this, converting buildings and vehicles to electricity is only part of the massive endeavor the state is working on to achieve net zero carbon emissions by 2050.
According to the Energy Information Administration, renewable energies currently make up about a quarter of the state’s total electricity generation, most of which is powered by small solar panel systems.
The climate legislation passed at the beginning of the year requires energy suppliers to procure an additional 2,400 megawatts of wind power, bringing the planned state procurement to a total of 5,600 megawatts. As a reference, the Vineyard Wind project will have a capacity of 800 megawatts – enough to supply more than 400,000 households with electricity. Construction should start this year.
At the same time, the country is working on an ambitious expansion of solar and hydropower.
How much does the power grid need to be expanded in order to switch from fossil fuels to electricity for cars and buildings?
In short, a lot. A study by the economic and regulatory research firm The Brattle Group found that electricity demand could be twice as high by 2050, when people switch to electricity for heating, cooling and their vehicles. This analysis was based on a previous target of 80 percent emissions reductions by 2050 rather than the current target of net zero emissions.
And it is not just the demand for electricity that has to grow. That will be the transmission system too. A 2020 study by Princeton University found that the grid would need to expand its transmission network by 60 percent by 2030 to meet the increased electricity demand resulting from meeting the net-zero emissions target triple by 2050.
The $ 1 trillion national infrastructure bill passed by the U.S. Senate earlier this month includes $ 73 billion for the nationwide power grid upgrade.
If people are now reluctant to switch entirely to electricity, are they still helping the climate by installing a heat pump but keeping a backup system?
Yes sir. According to Harvey Michaels, lecturer in energy management innovation at MIT and research director of Energy Management Practice and Innovation, homeowners who install a heat pump but still use a backup system will reduce their on-site CO2 emissions for heat by 50 percent 80 Percent.
And for a variety of reasons – be it the ability of a heat pump to keep a house warm enough or the high cost of installing heat pumps – people sometimes prefer to start small when making the switch. Experts believe that after the toe dip, more homeowners will eventually get rid of their backup systems completely.
There is one drawback, however. As Jeremy Koo, a senior technical and strategic consultant at Cadmus told us, keeping fossil fuel equipment in your home can decrease your ability to reduce emissions, and it also has an impact on the infrastructure that is in place to deliver fossil fuel supplies continue to support. “
I want to buy a heat pump – what is the first step?
A free energy assessment from Mass Save is a great first step, according to experts at Northeast Energy Efficiency Partnerships (NEEP) and Mass Save – the state’s state energy efficiency program. They’ll send an auditor to help highlight changes you can make to your home to run it more efficiently, including sealing drafty leaks and adding insulation – both things that can help improve heating. and reduce cooling costs.
Another thing to be aware of is your home’s electrical panel. If you want to buy heat pumps now, and an electric vehicle in five or ten years, you can save yourself costly electrical work by planning for those additional needs.
For more helpful advice, check out this story from Globe’s Janelle Nanos:
Where can I find contractors who can help?
The Massachusetts Clean Energy Center has a list of air source heat pump installers that could be a good place to start.
You can also take a look at NEEP’s Air Source Heat Pump Buying Guide for advice and a handy checklist of key questions to ask a contractor. “If your contractor says“ heat pumps don’t really work in cold climates ”or“ every heat pump needs a backup system ”, find someone else,” the instructions say. “Remember that the lowest bid is not always the best value for money and a high price does not guarantee competence or quality.”
Sabrina Shankman can be reached at [email protected] Follow her on Twitter @shankman.