Heat Pump Questions

doodling

Hi,

Reed_Richards said:

doodling said:

The reality is that if I add a 6kW (electrical) heat pump to my house today then the increase in electricity consumption will be met (in the short to medium term) by burning more gas, not by ramping up unused wind /solar / nuclear capacity (because there is none).

This makes no sense unless you explain what came before the heat pump.  

The context was in comparison to a gas boiler. And yes, selecting a heat pump will reduce CO2 emissions compared to a gas boiler (unless the additional load on the grid causes coal or OCGT generation to be used) but only by ~36%.

shinytop

doodling said:

Hi,

Reed_Richards said:

doodling said:

The reality is that if I add a 6kW (electrical) heat pump to my house today then the increase in electricity consumption will be met (in the short to medium term) by burning more gas, not by ramping up unused wind /solar / nuclear capacity (because there is none).

This makes no sense unless you explain what came before the heat pump.  

The context was in comparison to a gas boiler. And yes, selecting a heat pump will reduce CO2 emissions compared to a gas boiler (unless the additional load on the grid causes coal or OCGT generation to be used) but only by ~36%.

Is the 36% assuming the electricity the ASHP uses is 100% generated by burning gas? 

doodling

Hi,

shinytop said:

doodling said:

Hi,

Reed_Richards said:

doodling said:

The reality is that if I add a 6kW (electrical) heat pump to my house today then the increase in electricity consumption will be met (in the short to medium term) by burning more gas, not by ramping up unused wind /solar / nuclear capacity (because there is none).

This makes no sense unless you explain what came before the heat pump.  

The context was in comparison to a gas boiler. And yes, selecting a heat pump will reduce CO2 emissions compared to a gas boiler (unless the additional load on the grid causes coal or OCGT generation to be used) but only by ~36%.

Is the 36% assuming the electricity the ASHP uses is 100% generated by burning gas? 

Yes, in a CCGT. That is practically what will happen.

The overall mixture of power sources on the grid will change over time but for now extra electrical load = more gas generation (or maybe coal or OCGT gas in the winter).

I know I'm being unfashionable in my approach and am quite happy for others to adopt an approach based on an average generation mix if they want  but those people also then need to accept that additional loading makes that mix worse.

When we're in a world where we have excess wind power and the grid can cope with wind entirely pushing out fossil fuels then I'll agree with an approach based on average generation mix.