Air Conditioning Is the World's Next Big Threat
bloomberg.com
bloomberg.com
The answer is not to try to stop development - the answer is to cleanse the sources of electricity.
Add another 4000 kwh for heating around 50-150 m² (90-25 kWh/m² per year for a modern home in Germany).
In Germany you can use about 1.000 kWh/kWp per year from the sun, so one would need to install 60 m² of panels @ 20% efficiency for that.
The main problem is storage for the winter - or where am I wrong?
"Stop development" is a bit of an alarmist phrase. Few want that. Also, reducing demand in specific areas is still beneficial even if overall demand continues to increase. There's no reason not to address both demand and supply.
If you lived in a hot climate (like India, which is one of the countries TFA referred to as a source of high future demand), then you'd understand just how crazy of an idea that is. (side note: your profile links to a site with a bio claiming that you live in Massachusetts. I rest my case.)
Look, it's not that the idea has zero merit. There are architectures which do a better job at keeping the interiors cool, and incentives could be set up to favor those designs. But such designs are also usually bone-cold in the winter, and you see energy usage pendulum-swing back to high in other parts of the year. Plus, locales with hot weather typically have local architectures with these kinds of "natural cooling" features anyway, so it's usually not anything new.
There's a reason why I think calls to reduce air conditioning to be anti-development, and it's because I happen to live in one of said climates, and there's no way I'd get anything done without air conditioning. Unless we want to keep the underdeveloped regions of the world in poverty, increased demand for air conditioning is simply inevitable.
Meanwhile air conditioning is considered a luxury even if lack of it also results in people dying - both are of course on a spectrum in terms of necessity depending on circumstances.
This is a common misconception- electrically resistive heat generation is not the most efficient way to heat a room with electricity. Rather, you can move about two to three times more heat per unit energy using a heat pump than you can with simple resistive heating.
This is why you get over 100% efficiency in terms of work vs output.
Say you have a 100% efficient heater it means for every watt you put in a watt of heat is released to the environment.
A heat pump doesn’t releases anything it moves it from one side to another so for one watt of energy that it takes to operate a heat pump you can move up to 10 watts worth of heat (some pumps can be even more efficient than this) form one side to another.
https://www.engineeringtoolbox.com/air-conditioner-efficienc...
> you also can't say 'just don't use heat' without looking idiotic
Can't you put on a sweater to minimize your energy footprint?
> air conditioning is considered a luxury
Isn't air conditioning common even in developing countries? Perhaps it is luxurious to cool your environment, but to what extent is it a luxury?
> even if lack of it also results in people dying
Are people dying from lack of air conditioning? Will people die without it? I find it is difficult to argue causation of death due to lack of a luxury
This is a common misconception. AC is far above 100% efficiency because it moves heat rather than creating it. Maintaining a 30 degree temperature difference (say 40->70F) using traditional heat is far more energy demanding than air conditioning from 100->70F. The difference is big enough that HVAC costs in a scorching desert climate like Dubai are lower than much of northern Europe.
Heat pump based heating moves heat like AC, but efficiency drops the greater the temperature difference between inside and outside. Most cold climates are too cold for heat pumps to work for much of the year. On the other hand even the hottest climates don't have a temperate Delta of more than 40F inside to outside on the hottest days. So air conditioning is still in the efficient heat pump operating band.
Electricity costs due to AC are typically at least 3x more in the summer than gas costs due to heating.
Edit: I shouldn’t have written all parts of the US, but wherever you’re trying to bring temperatures down just as much as you’re trying to bring them up in winter.
The cold feeling is two fold. The lower humidity helps almost as much as the temperature drop in humid areas.
Heating doesn't cause the water vapor phase transition so sealing out humid air matters little for efficiency. This is why many older buildings have higher cooling than heating costs. Sealing is just as important as insulation when cooling
There's no reason a heat pump can't heat a house and water as well as cooling it. Gas doesn't even run at 100% efficiency as some of that heat is disappearing out the flue.
So unless gas is under a quarter of the price of electricity it should pay, and pay well...
>In most cases, an experienced HVAC technician will opt to install a furnace over a heat pump if they have access to natural gas. The exception to this is when a home is located in the coastal areas of California and the gulf states.
>Because heat pumps are transferring heat from one area to another, what happens if it is -20 degrees outside in the middle of a North Dakota winter? Is there any heat to transfer into your house? That’s the catch.
>A heat pump only works well if the temperature is above freezing, and is almost useless in the middle of a harsh northern winter. Ideally a heat pump is used when the temperature outside is over 40-50 degrees fahrenheit (and are VERY inefficient below 30-32 degrees), so heat pumps are out if you live in Montana unless you also have a supplemental means of heating your house. In fact, heat pumps are actually designed for coastal climates in the southern states. So what do people in Bozeman, Montana do? They use a furnace, or a wood-burning stove!
Heat pumps are pretty common in Scandinavia, and readily available in Canada and other cold places. I found this on a Canada gov website: "At –8.3°C, the COP is typically 2.3". So at 17°F in American money, that's 2.3kW out for every 1kW in, and air source is the least efficient type.
https://www.nrcan.gc.ca/energy/publications/efficiency/heati...
Heat pumps for heating do degrade in efficiency as temperature drops, but stay cost effective down to -15°C, or -20°C or so. Supposedly, newer ones go even lower still. With ground source you just dig a bit deeper, as assuming we're not talking permafrost it's fairly easy to reach efficient temperatures.
Cold areas usually have a mostly unused backup heater in heat pumps, for those few times record breaking cold arrives, and of course the nearer you get to a COP of 1 (1kW in = 1kW out) the longer it takes to pay back the extra cost.
Gas heat is cheaper than ever. But as long as you're not in an extremely cold area heat pump is probably cheaper. In your case, it might make sense to keep the furnace for days too cold for the heat pump to work efficiently. Use it as supplemental heat.
In days when temperatures are >40F the heat pump would be ~6X more efficient at moving BTU than gas heat. You can use online calculator to work out the BTU of gas used vs electricity cost. There's definitely a lower temp limit where gas is cheaper, but also a good chance your climate doesn't hit that temp often
Doesn't climate change lead to extreme temperatures in both directions though?
(If the article covered this, my apologies - I couldn't read the whole thing without having to pay).
But the overlap is not perfect. Typically the hottest part of the day is a few hours after solar peak, and it's often still hot after the sun goes down. So you still need storage and/or grid power for complete A/C coverage.
It seems that people could burn a few calories and generate substantial kilowattage with a bit of clever engineering.
Same concept applied to an Archimedes pump bringing seawater to the top of a gravity-driven reverse-osmosis purification plant could increase arable land.
Sounds like we're several innovations away.
Let's put Elon Musk on the task.