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People Living in the Hottest Places on the Planet Are the Least Likely To Have Air Conditioners (qz.com)
Zoe Schlanger, writing for Quartz: In 2016, roughly 10% of the planet's energy use went towards air conditioning. Figures vary wildly from country to country, though, and some of the hottest regions on Earth use the least A/C -- for now. A new report from the International Energy Agency says that's about to change. By 2050, the intergovernmental agency predicts, global energy use from A/Cs will triple, reaching a level equivalent to China's total electricity demand today. The African continent is home to some of the hottest places on Earth, but fewer than 5% of people in most African nations own an air conditioner, and energy used for cooling comes to just 35 kWh per person living in the continent, according to the IEA. In India, where large parts of the country are hot all year round, people use an average of 70 kWh for cooling. Compared to nations where having an A/C is the norm, that's almost nothing at all.
Air conditioning is not a luxury, crappy insulation is! Look at most of the buildings in the US and they are badly insulated if at all. Also does not help that even new construction is using popsicle sticks and office supplies. Brick fares much better to keep buildings cooler in the summer and warmer in the winter.
So you are saying that India is not an overcrowded country where people bathe in the Ganges and treat cows as sacred?
Why must we pretend that India is a great place to live when it sucks?
http://www.dry-it-out.com/cool...
A 10m x 10m room x 2m ceiling requires 12KW to cool it. I made the numbers easy to simulate an entire house and give 100sq meters of panel.
https://dothemath.ucsd.edu/201...
A standard solar panel produces about 250-300W per square meter in such regions. Therefore you'd need about half your roof space to cool just one room, and nothing else. Call it a two-storey house (upstairs and downstairs) and you can *just* about cool the house if you do nothing else with it.
https://news.energysage.com/12...
"As of January 2018, the average cost of solar in the U.S. is $3.14 per watt ($37,680 for a 12 kilowatt system). That means that the total cost for a 12kW solar system would be $26,376 after the 30% Federal ITC discount"
You would literally be spending something on the order of $35k just to cool your house. That's an annual wage. If you can't afford the air-con (notice that the article is just as much about "poorer countries can't afford air con, hotter countries cost even more to air con), $35k on top of the investment to power it is a huge amount.
https://www.ovoenergy.com/guid...
That would buy 437,500 KWh of electricity in India, for example, which would keep that same 12KW powered for.... 99 years.
What you're asking is "Why can't people just spend 100 years of their cooling electricity usage in one hit so that they don't have to pay for any more cooling? On top of the price of the cooling system, and not including maintenance, replacement, fitting, etc. of either."
Care to share those miraculous methods?
what's the average temperature during the summer where you live?
where i live it's 30C. with 40C days and 30C nights for weeks at a time. with 80-90% humidity to top it off.
so yeah if you can tell me the secret to keep cool without AC during those times, I will take your point. otherwise, it's as stupid as saying "heating is a luxury, you only need to add more layers of clothing"
A 10m x 10m room x 2m ceiling requires 12KW to cool it.
Seriously? Where, on Venus? Or using American "insulation"?
As of January 2018, the average cost of solar in the U.S. is $3.14 per watt ($37,680 for a 12 kilowatt system).
Get lost. This is not about the mind-bogglingly ovepriced US residential solar. Even in Europe, you're somewhere around $1.2/W today. In the developing world, you're practically talking about hardware costs, which are below $1/W for both panels and an inverter (or perhaps just $0.4/W for the panels, plus structures and labor, if you happen to have DC equipment).
That would buy 437,500 KWh of electricity in India
Except for the time when everyone's AC turns on and the notoriously unreliable Indian grid breaks down. So basically it isn't there when you need it most. Not to mention that the utilities can build a large system and then have you pay for it in those $0.08/kWh. Seriously, it's their cheapest option by now anyway.
Ezekiel 23:20
The state of South Australia can get very hot. It recently went through an energy crisis, leading to a deal with Elon Musk to provide batteries to help even out power demand. This might be a small scale example of what's to come. South Australia has a tiny population compared to India, so a lot of research will need to happen focusing on new ways to generate, store and distribute energy if a demand for summertime A/C takes off there.
The cool thing (punny) is that would drive down the cost of batteries, solar panels, or whatever technologies are in large scale use, making them cheaper for the rest of us (assuming production can keep up).
"How much truth can advertising buy?" - iNsuRge - AK47
(Judging by the summary) the authors of the report are projecting that added air conditioning in currently underserved areas will use energy-hungry heat pumps, like developed world city and suburbs currently do. This ignores recent (and any yet-to-come) technology breakthroughs.
One is M-cycle cooling systems like Coolerado's. In locations where a swamp cooler would work, and many where it would fail due to moderately-too-high humidity, an M-cycle cooler will deliver cool air using about twice the power needed to blow it around and a little water (less than the amount saved by some power plant not generating the added electricity to power a heat pump, so you're AHEAD on water use, too). The air delivered does not have added humidity (just the higher relative humidity from cooling it, which WON'T drop it below the dew point and get mold going indoors), nor does it have added bacteria (though the half exhausted outdoors still may).
The guts of the Coolerado version is a "mass-heat exchanger" - a stack of plastic sheets that gets water (with a trace of soap) injected on one port, outside air blown in another, cooled air coming out a third, wet air out a fourth, and an unevaporated fraction of the water with the minerals and such out a fifth. Cheap (or it can be if the patent holders chose). Already being used in, among other places, medical facilities in India.
Another is the "infrared window" approach. Think "solar panel" that dumps about 90 watts per square meter of heat energy into the sky 24/7, (slightly better at night than noon). Cheap version of a plastic film with a silvered backside and 10-ish micron glass beads embedded in it. Only reason you need any power at all is to control the transfer of heat from the room to the panels (say, by circulating a heat-transfer fluid and blowing air through a radiator), so you don't get more cooling at night (when you probably don't want any) than at noon or afternoon (when you want a lot).
Not only can these, and potentially other approaches, provide air conditioning for the developing world at a fraction of the energy cost (and perhaps the equipment cost) of a classic heat-pump system, but they can also reduce the energy cost of cooling in the developed world.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
In thinking about the high-calorie foods that would make our coder-drone selves become obese, I got to wondering where recipes for things like fried chicken and pecan pie came from and what social purpose to they serve?
Pre-mechanization, the use of horses was a productivity enhancer over human labor but even over draft animals such as oxen that are used throughout the world, past and present. An ox has pulling force, but a horse owing to its higher capacity cardiovascular system has a lot more power output, and the use of horses over oxen in agriculture was a breakthrough.
Likewise, the consumption of high-calorie foods by farm workers as opposed to having them get by with a minimum-calorie subsistence diet that is the norm in many parts of the world is also a productivity enhancer.
It has been said that air conditioning kindled the economic growth of the American South, or at least the southward migration of Yankees. Yes, one can subsist at a poverty level on minimal calories and natural outdoor temperatures, but think of the increased work, both physical and mental, one can do with enough to eat and respite from the heat? And think of this as breaking out of subsistence-level poverty?
The original poster is correct. Before air conditioning, passive thermal building design was de facto. You put up awnings to keep out summer sun, but the winter sun comes in at lower angles and you make sure it goes through the window and heats up some dense mass - masonry, tile, a brick hearth, etc. Likewise, highly reflective roofs, southern walls ribbed like a saguaro cactus to prevent the sun from hitting much of the wall at once, geothermal ducting combined with windcatcher chimneys and convection - these have been known tricks for thousands of years.
I'm just shaking my head at the know-it-alls calling all this magical. It's been concrete knowledge for longer than there's even been concrete.
Three things:
1. Today I can buy 250w panels in the UK for ~79cents/watt, or a little under $9500 for 12KW at today's exchange. Bearing in mind that the price that you or even I pay is likely to considerably higher than the price of panels in "third world countries" - for the same reasons that power is cheaper. At MW scale the price is even lower.
2. I am not necessarily advocating panels on housing (although Germany is currently experimenting with estate built housing all with solar roofs and also estate battery systems (but not necessarily on the same estate)). If you visit Germany, you see MW sized solar panel systems built on all sorts of otherwise marginal land - all over the country. Here in the UK, it is actually more profitable to farm MW sized solar panels than crops on anything less than grade 2 land and there are many 100s of such installations all over the country, even though the UK has notoriously erm.. variable weather. Imagine what could be done in countries in sunny climates.
But the point is that increasing scale pushes the overall price down and, crucially, balances the majority of the aircon load - reducing the overall emissions for aircon is a happy by product.
3. In India, even dyed in the wool coal fired power plant companies are seeing the writing on the walls and are actively building double (and a few triple) digit solar plants. There must be money to be made here otherwise they would not bother.
Sure, I already have. See:
http://sugarmtnfarm.com/cottag...
and
http://sugarmtnfarm.com/butche...
You'll find a lot of articles discussing the design, construction, operation and plenty of photos.
We're in USDA Zone 3.
Summer high of: 30ÂC (86ÂF)
Winter low of: -42ÂC (-45ÂF)
Our butcher shop says cold enough that we do not have any mechanical refrigeration for the building. I have spaces I'll eventually make into walk-in coolers but we got our USDA license without that. In fact, the USDA regional head was extremely impressed with our facility and told me so. We passed our licensing on the first try with a 100% score, because it was built right and then operated right. I'm meticulous. The butcher shop is about 1.6 million pounds of masonry built in six shells one within the other with insulation between each such that the freezer at the center has R-120. The reason for six shells is that each is a different temperature zone and the tend to float towards their ideal. This is a large flywheel that lets me use the seasonal outdoor air temperatures controlled by vents to achieve the temperatures I want, almost. There is space for a coolth attic where someday I'll build brine tanks to store winter's cold using thermal loops. This is above the coldest parts of the building so passive loops can be used both to chill the brine tanks and to chill the rooms below. See: http://sugarmtnfarm.com/butche...
Our house stays comfortably cool all summer long. High windows vent allowing cross winds. The shape reduces solar gain. This is pretty standard stuff but unfortunately not used widely enough in modern construction. In our house, which is 252 sq-ft, the total thermal mass is 100,000 lbs of masonry inside the insulating envelope and quadruple glazing on the windows. See: http://sugarmtnfarm.com/cottag...
Neither my house nor my butcher shop freeze in the winter despite our long cold season even when not heated. I do not heat my butcher shop at all. In the winter I am dumping accumulated summer heat to the sky so that it can coast through the next summer. In our house I use a bit less than 0.75 cord of wood in a small masonry stove to bring the indoor up from about 45ÂF (7ÂC) to 72ÂF (7ÂC) during the winter as my wife likes it a little warmer. However that is a luxury, the heating, and not needed since neither building will freeze. A key thing is that rather than heating the air, as in conventional wood studded construction, I'm heating the masonry.
Neither building requires electricity to perform thermally. This is an important detail in our location because we get about two weeks of electrical outages a year, primarily in the colder half of the year.
Most people could implement this for homes and businesses. The major problem is that our current government systems subsidizes wasteful uses of energy so energy is too cheap. If energy were more expensive then people would work harder at conservation.
No magic.
No miracle.
Just science applied to real problems.
Despite the belief of some, the US is not "the rest of the planet" after the UK. :-p Meanwhile, even in Central Europe, prices around $0.55/W post-tax are not unheard of. Hardware costs are not really an issue anymore.
Ezekiel 23:20