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This. Also, AC needs energy during clear summer days - exactly when it’s the cheapest to deliver by PV. With minimal effect on climate.

masklinn 4y ago
An interesting side-effect although sadly not leveraged much in the US, and also little used in europe because of the stigma on AC, is that AC is a heat pump and heat pumps are reversible. It’s finally gaining in popularity, and depending on weather conditions a modern heat pump can provide heating several times more efficient than straight up burning fuel even if you’re producing electricity from that fuel. When your electricity is nuclear or hydro (or other renewables but that tends to be a bit sticky in winter) it’s manna.
- pfdietz 4y ago
  It's a travesty that A/C units in the US are not (in many cases) designed to be reversible. I mean, even if you have a gas furnace, using the heat pump when it's only mildly cold can be cheaper.
zdragnar 4y ago
This is really not true. Case in point, today where I am it will be overcast, 85*F, and very high humidity. We also get extreme cold in winter, so there's no getting around needing both AC and heating, but solar isn't a panacea. Unfortunately, hot cloudy days also don't tend to produce much wind either.
- kolinko 4y ago
  I may be wrong but isn’t this an exception, not a rule?
  - zdragnar 4y ago
    A bright sunny summer day will be hotter, but there's nothing magical about clouds that makes the need for air conditioning disappear unless you live in a desert.
    - kolinko 4y ago
      At least in my region (central Europe) cloud cover is closely correlated with temperature. As in - when clouds and rain come during summer it gets colder as well. I may be wrong here, no scientific data behind this.
- saltcured 4y ago
  The AC system is not consuming the same energy in an overcast day versus an intensely sunny day, even if the outside air temperatures are comparable. The direct radiant heating of the structure with sun exposure introduces much more heat than the mere conductive transfer from outside air. When people say that AC costs correlate with solar power, they are pointing out that the same solar energy that increases heat gain for buildings during the bright hours also increases photovoltaic output which can be used to compensate for that heat gain.

masklinn 4y ago

An interesting side-effect although sadly not leveraged much in the US, and also little used in europe because of the stigma on AC, is that AC is a heat pump and heat pumps are reversible. It’s finally gaining in popularity, and depending on weather conditions a modern heat pump can provide heating several times more efficient than straight up burning fuel even if you’re producing electricity from that fuel. When your electricity is nuclear or hydro (or other renewables but that tends to be a bit sticky in winter) it’s manna.

pfdietz 4y ago
It's a travesty that A/C units in the US are not (in many cases) designed to be reversible. I mean, even if you have a gas furnace, using the heat pump when it's only mildly cold can be cheaper.

zdragnar 4y ago

This is really not true. Case in point, today where I am it will be overcast, 85*F, and very high humidity. We also get extreme cold in winter, so there's no getting around needing both AC and heating, but solar isn't a panacea. Unfortunately, hot cloudy days also don't tend to produce much wind either.

kolinko 4y ago
I may be wrong but isn’t this an exception, not a rule?
- zdragnar 4y ago
  A bright sunny summer day will be hotter, but there's nothing magical about clouds that makes the need for air conditioning disappear unless you live in a desert.
  - kolinko 4y ago
    At least in my region (central Europe) cloud cover is closely correlated with temperature. As in - when clouds and rain come during summer it gets colder as well. I may be wrong here, no scientific data behind this.
saltcured 4y ago
The AC system is not consuming the same energy in an overcast day versus an intensely sunny day, even if the outside air temperatures are comparable. The direct radiant heating of the structure with sun exposure introduces much more heat than the mere conductive transfer from outside air. When people say that AC costs correlate with solar power, they are pointing out that the same solar energy that increases heat gain for buildings during the bright hours also increases photovoltaic output which can be used to compensate for that heat gain.