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"The electricity to run a heat pump that moves heat where you want it is cheaper than the gas you need to burn to make an equivalent amount of heat." This must

"The electricity to run a heat pump that moves heat where you want it is cheaper than the gas you need to burn to make an equivalent amount of heat." This must depend on the relative prices of gas and electricity. What's the threshold ratio beyond which gas is cheaper than a heat pump?

hedora 4y ago
It generally takes less gas to generate electricity, ship it, and run the heatpump than to directly heat the house with gas.
- rahimnathwani 4y ago
  But I don't generate or ship electricity. I buy both my electricity and my gas from PG&E, and pay whatever price they charge for each. So the question of which is cheaper depends not on the fundamentals of physics of it, but on the relative prices PG&E charges for each.
  - hedora 4y ago
    In California, the heat pump will win, partially due to the mild climate, and partially due to natural gas somehow being even more overpriced than electricity.
    - rahimnathwani 4y ago
      I pay PG&E: * ~$0.35/kWh for electricity * ~$2/therm for gas (equivalent to ~$0.07/kWh according to a quick search). Even though I pay 5x the price for electricity as I do for gas, a heat pump will be cheaper?
      - hedora 4y ago
        You get a lower rate (higher baseline) if you install a heat pump ($0.28-0.30; 4x to 4.2x), and the coefficient of power for the heat pump should be well over 4 in California. Current electricity rates: https://www.pge.com/pge_global/common/pdfs/rate-plans/how-rates-work/Residential-Rates-Plan-Pricing.pdf https://www.pge.com/pge_global/common/pdfs/rate-plans/how-ra... Current natural gas rates: https://www.pge.com/tariffs/GRF1122.pdf https://www.pge.com/tariffs/GRF1122.pdf You seem to be on the cheaper residential schedule.
        rahimnathwani 4y ago
        > You seem to be on the cheaper residential schedule. I'm in San Francisco, so PG&E bills me separately for distribution (provided by PG&E) and generation (provided by CleanPowerSF). We are on a rate plan that has slightly cheaper electricity off peak, and save something like $20/year as a result. The individual line items on the bill are hard to understand (lots of surcharges and credits), but I can tell you from the totals that my most recent bill shows $0.33 per kWh for electricity (average, including both delivery and generation) and $2.56 per therm for gas.

hedora 4y ago

It generally takes less gas to generate electricity, ship it, and run the heatpump than to directly heat the house with gas.

rahimnathwani 4y ago
But I don't generate or ship electricity. I buy both my electricity and my gas from PG&E, and pay whatever price they charge for each. So the question of which is cheaper depends not on the fundamentals of physics of it, but on the relative prices PG&E charges for each.
- hedora 4y ago
  In California, the heat pump will win, partially due to the mild climate, and partially due to natural gas somehow being even more overpriced than electricity.
  - rahimnathwani 4y ago
    I pay PG&E: * ~$0.35/kWh for electricity * ~$2/therm for gas (equivalent to ~$0.07/kWh according to a quick search). Even though I pay 5x the price for electricity as I do for gas, a heat pump will be cheaper?
    - hedora 4y ago
      You get a lower rate (higher baseline) if you install a heat pump ($0.28-0.30; 4x to 4.2x), and the coefficient of power for the heat pump should be well over 4 in California. Current electricity rates: https://www.pge.com/pge_global/common/pdfs/rate-plans/how-rates-work/Residential-Rates-Plan-Pricing.pdf https://www.pge.com/pge_global/common/pdfs/rate-plans/how-ra... Current natural gas rates: https://www.pge.com/tariffs/GRF1122.pdf https://www.pge.com/tariffs/GRF1122.pdf You seem to be on the cheaper residential schedule.
      - rahimnathwani 4y ago
        > You seem to be on the cheaper residential schedule. I'm in San Francisco, so PG&E bills me separately for distribution (provided by PG&E) and generation (provided by CleanPowerSF). We are on a rate plan that has slightly cheaper electricity off peak, and save something like $20/year as a result. The individual line items on the bill are hard to understand (lots of surcharges and credits), but I can tell you from the totals that my most recent bill shows $0.33 per kWh for electricity (average, including both delivery and generation) and $2.56 per therm for gas.