There doesn't appear to be any actually sensible evidence in the article?
> I also remember getting similar tips from PG&E here in California.
Company that sells you energy telling you to not stop consuming energy...
Aside from that, I'd imagine they also want to limit power usage spikes. Everyone coming back from the weekend then running AC on the full blast just consumes a lot of power.
Our office was actually given same advice (just leave AC running over weekend) but it was explicitly said it was to avoid power usage spikes, as cooling back down space that big just takes a lot of power for a long time.
There might be some truth about saving money, if say the rate for power when you'd be turning AC back on is high, vs having that spread over lower rates, but certainly not kWh, at least not if you go out for a whole day or two.
> Do you have any citations as to why turning off AC/heater is better than leaving them on when we leave home?
Basics of thermodynamics ? I think easiest comparison would be boiling water. What makes more sense, to turn off a pot of boiling water after making tea, or to keep it running till you want next cup of tea? You can keep it running to get the next tea instantly ready, or turn it off to not.
It's the same for AC. Turning it off saves power, but it will take longer to get back to the cold state)
You need to keep moving energy (whether heating or cooling) to/from the system to keep it at temperature different than ambient.
The bigger the difference, the more energy needs to be moved.
Keeping AC on constantly is like keeping a pot boiling, you need to pump that energy constantly.
Turning it off means that you stop, and while yes, you have to dump more power to get back to the desired temperature, you save all that power that you'd need to use to keep it at previous temp.
> There might be some truth about saving money, if say the rate for power when you'd be turning AC back on is high, vs having that spread over lower rates, but certainly not kWh, at least not if you go out for a whole day or two.
That might be the main reason behind PGE's suggestion - they charge more for 4-9pm usage and it is much cheaper to pre-cool the house between 12-2pm when the demand is lower.
> I also remember getting similar tips from PG&E here in California.
Company that sells you energy telling you to not stop consuming energy...
Aside from that, I'd imagine they also want to limit power usage spikes. Everyone coming back from the weekend then running AC on the full blast just consumes a lot of power.
Our office was actually given same advice (just leave AC running over weekend) but it was explicitly said it was to avoid power usage spikes, as cooling back down space that big just takes a lot of power for a long time.
There might be some truth about saving money, if say the rate for power when you'd be turning AC back on is high, vs having that spread over lower rates, but certainly not kWh, at least not if you go out for a whole day or two.
> Do you have any citations as to why turning off AC/heater is better than leaving them on when we leave home?
Basics of thermodynamics ? I think easiest comparison would be boiling water. What makes more sense, to turn off a pot of boiling water after making tea, or to keep it running till you want next cup of tea? You can keep it running to get the next tea instantly ready, or turn it off to not.
It's the same for AC. Turning it off saves power, but it will take longer to get back to the cold state)
You need to keep moving energy (whether heating or cooling) to/from the system to keep it at temperature different than ambient.
The bigger the difference, the more energy needs to be moved.
Keeping AC on constantly is like keeping a pot boiling, you need to pump that energy constantly.
Turning it off means that you stop, and while yes, you have to dump more power to get back to the desired temperature, you save all that power that you'd need to use to keep it at previous temp.