Climate risks heat up as world switches on to air con

[Aurora]

The Guardian - 10/07/12

The US has long used more energy for air conditioning than all other nations combined – but that's about to change.

Article continues ...

[RenewableCandy]

God that's depressing. AirCon is a disease.

[snow hope]

Right, air con uses electricity to cool living accomodation in hot climates.

We live in a temperate/cool climate and we use heating for 4 or 5 months every year (of whatever type) and don't really need air con. This year we have been lighting out stove in May, June and July.

But I am partial to enjoying a week or two in the south of Spain from time to time - haven't been for about 3 or 4 years, but may get away in August I hope. I love the guaranteed heat, sunshine, and warm climate, compared to our wet and cool crap!

But having stayed in accomodation without air con and experienced how difficult it can be to sleep when it is way too hot for normal human beings, I can understand why people who live in hot climates might want to use air con to cool their living accomodation down.

The last few times we have been to the South of Spain, we would not go unless we were sure that the accomodation included air con.

Just offering up another perspective... not saying it is right, but maybe they think it is wrong we heat our houses for 5 months a year??

[RenewableCandy]

Passive cooling isn't that difficult in a place like Spain, with dry heat. But the buildings have to be made that way from the start. What this article is lamenting is that the spread of air-con will tempt people into putting up cheap crappy buildings that are simply unusable without it, thus locking the rest of the populace into expensive, damaging and unhealthy (because let's face it, no-one changes the filters often enough) air-con.

When I was in China it hit 38 degC every day. I slept under a large towel. I don't know why, but no matter how hot it was, that kept me cool enough to sleep. And there weren't even fans, let alone air-con: this was 1988.

[Tarrel]

Passive cooling isn't that difficult in a place like Spain, with dry heat. But the buildings have to be made that way from the start. What this article is lamenting is that the spread of air-con will tempt people into putting up cheap crappy buildings that are simply unusable without it, thus locking the rest of the populace into expensive, damaging and unhealthy (because let's face it, no-one changes the filters often enough) air-con.

When I was in China it hit 38 degC every day. I slept under a large towel. I don't know why, but no matter how hot it was, that kept me cool enough to sleep. And there weren't even fans, let alone air-con: this was 1988.

+1

Regarding the towel, it may create a micro-climate around your body, potentially affecting the evaporation of sweat and, hence, cooling. The Tuareg in the Sahara take a similar approach, swathing themselves in robes and head-gear to create a micro-climate, in this case a damp one, which reduces the evaporation of sweat and hence dehydration, that would otherwise occur in the ultra-dry, windy environment.

I have a friend in Saudi Arabia who is an architect. He designs new housing developments along traditional lines, i.e. thick walls, high thermal mass, built around a courtyard into which the doors and windows face. They don't need aircon, but just in case, they have a roof terrace on which people can sleep on some of the hottest nights.

[Tarrel]

We live in a temperate/cool climate and we use heating for 4 or 5 months every year (of whatever type) and don't really need air con. This year we have been lighting out stove in May, June and July.

Agreed, but it's interesting to note that, where we used to live, deep in the Hampshire suburbs, a surprising number of houses were sprouting air conditioning units. Crazy! (They were usually the ones with the largest arrays of solar PV on their roofs)

[snow hope]

Passive cooling isn't that difficult in a place like Spain, with dry heat. But the buildings have to be made that way from the start. What this article is lamenting is that the spread of air-con will tempt people into putting up cheap crappy buildings that are simply unusable without it, thus locking the rest of the populace into expensive, damaging and unhealthy (because let's face it, no-one changes the filters often enough) air-con.

When I was in China it hit 38 degC every day. I slept under a large towel. I don't know why, but no matter how hot it was, that kept me cool enough to sleep. And there weren't even fans, let alone air-con: this was 1988.

Fair enough then, sorry, missed the link to the cheap buildings that depend on air con.

[adam2]

I dont consider air conditioning any worse than heating.
Both use fuel to make the indoor enviroment more comfortable.
The use of either should be minimised, and be renewably powered whenever possible.

Good design and passive cooling helps to an extent, but in some recent years in London, the overnight temperatures have been so high that passive cooling wont work.

I use air conditioning, though it is 100% PV powered, and IMHO far preferable enviromentaly to excessive FF burning central heating.

The greatest demand for cooling at least roughly coincides with peak PV availability, making grid tied PV ideal for offsetting energy used for A/C.

Heating demand can be reduced by insulation, by heat recovery, and by wearing warm clothes.
The options for dealing with excessive heat are more limited.
Insulation helps little when it is 30 degrees inside AND outside.
There is a limit to what clothing can be discarded in most situations.
Heat recovery does not help when one is trying to dispose of heat, not to save it !.

With a warming climate, A/C is going to be needed more, not less.
Best to encourage moderate and responsable use, and the offsetting of the energy used by renewable generation.

[adam2]

30 degrees outside at present in London.
Inside temperature at home should be about 25/26, as I have left the A/C on, but at the highest temperature setting. Mainly for the cats, they like it warm but dont seem to like much over 26.
Fuel used is zero as is 100% PV powered, and I have loads to spare in this weather.

At work in my deepest, darkest, security dungeon it is 24 degrees without any cooling, OK for sitting down in front of a fan, but too warm if any physical work is needed. The A/C unit would easily cool this down to 20 or below, and I use it sparingly as needed. It uses about 1KW.

Not so pleased about the rest of the building though I have been instructed to turn on the central chiller plant because some managers are working today.
Energy used is about 1,000KW* for a large office building.
Or about £150 an hour.
£150 or so an hour is arguably well worth it when the building is fully occupied with perhaps 2,000 persons or more, (my estimate, multi tenanted office building) It is only a few pence per hour per head.
Seems a lot though for only a dozen or so persons.

*the total load is more than twice this figure, but the plant is thermostaticly controlled and would only use full power continually in very hot weather, and with a full occupancy.
In a previous heatwave, the power required was in excess of that permitted to be drawn from the grid, and we had to run the standby diesel generator as well.

[biffvernon]

Fuel used is zero as is 100% PV powered, and I have loads to spare in this weather.

There's an opportunity cost. If you put your 'spare' electricity into the grid then some gas would not be burnt in the constant load-following dynamic.

Cats can find the shade.

[Kentucky Fried Panda]

I don't think homes are that much of an issue. If you work in an office it's most likely air conditioned and that power is used during peak demand times.

Heat pump air conditioning is used for heating a lot more commercial buildings these days.
If you had a heat pump system at home and it was well insulated with a good controls strategy, it's possible you could use less energy to heat your house in the winter.

[biffvernon]

A better strategy when it's hot is to head to the beach.

[JohnB]

A better strategy when it's hot is to head to the beach.

Can you define hot please. I thought today was supposed to be the hottest day of the year. If it was, air conditioning will never be needed in this part of the world!

[adam2]

Fuel used is zero as is 100% PV powered, and I have loads to spare in this weather.

There's an opportunity cost. If you put your 'spare' electricity into the grid then some gas would not be burnt in the constant load-following dynamic.

Cats can find the shade.[/quote

True in theory, but my system is a stand alone battery charging one, without any grid connection.
Can not export power to the grid without all sorts of costs and complications.

Cats can find the shade, and normaly do, but today was very hot even in the shade.

[biffvernon]

Ah, well in the case of a stand alone system I'd be tempted to use the spare electricity for cooling the beer rather than the cat. They come from Egypt!