How many US homes could add heat pumps within today’s winter grid headroom, and how that could lower electric rates and emissions.
  • partial_accumen@lemmy.worldEnglish
    10·
    6 days ago

    My solar PV system was one the reasons I went ahead and ripped out the gas furnace and put in a cold climate heat pump. No amount of solar generation lowered the gas bill, but with the heat pump that is yet another bill that is paid for largely by the panels on the roof. The continued rising costs of gas was another incentive to remove the low efficiency contractor grade gas furnace. In the USA we were also able to take advantage of the tax credit to pay for part of the heat pump installation before trump did away with the credit.

    Can I ask what fuel you’re using to heat your house now? Also do you have AC for cooling in your house already?

    • DevDave@piefed.socialEnglish
      1·
      2 days ago

      A mixture of electric and natural gas. Natural gas to bring the whole house up to ~65F (~18.3c) and then I have electric radiators to make only the areas I am using comfortable.

      That usually trends $120~$150/month in natural gas or around $1000/year. Financing a heat pump + installation could be $170 to $200 month in payments for 15 years.

      I know the price of natural gas is going to sky rocket relatively soon but as Terry Pratchett’s boot theory illustrates, it is expensive being poor.

      • partial_accumen@lemmy.worldEnglish
        1·
        2 days ago

        and then I have electric radiators to make only the areas I am using comfortable.

        While electric radiators are 100% electricity efficient (meaning 100% of the electrical energy turns into heat), they are very far away from an economical way to create heat. I understand the cost of a central heat pump can be expensive. If you’ve already modeled your heat use around specific smaller spaces to heat to comfort level, you may benefit from a small window mounted heat pump that costs $340.. The one I linked here shows a power consumption of 800 Watts (on a better site). If you’re in the USA, your electric resistive heaters are likely drawing 1500w.

        Here’s how that would translate to energy consumption costs (assumptions: you pay 25 cents per KWh of electricity):

        • Electric resistive heater running full blast (5,118 BTUs per hour) for 24 hours: 36KWh x .25 cents = $9 in electricity cost per day to produce 122,832 BTUs in a day
        • Window heat pump running full blast for 24 hours: 19.2KWh x .25 cents = $4.8 in electricity cost per day to produce 192,000 BTUs in a day

        So this unit would cost just about half the electricity to run, and produce 36% more heat! Obviously neither heater would be running full blast for 24 hours, and the heating efficiency will vary depending on how cold it gets outside, but the savings would likely still be substantial. You might even be able to run the window heat pumps longer and use less natural gas. More expensive than a window unit, but still far cheaper than a central heat pump would be a mini-split. These are usually even slightly more efficient and far cheaper than central heat pumps.

        Considering you’ve already got a PV solar setup, your solar power would go significantly farther in reducing your monthly energy bills.