101–110 of 349 posts
Earlier quoted context omitted.
If you're in the US, you can likely save much more than 30% today by replacing a central air system with a ductless mini-split style system. These are already dominant in the rest of the world, however.
What makes them so much more efficient?
Trump's 2018 budget zeroes funding for Energy Star, which among other things, helps consumers pick the most efficient devices, save money in the long run. What other ways can consumers compare the efficiency of A/C units? I would think some standardized testing and labels would be required.
There are standardized efficiency measurements that all A/C manufacturers must conduct and publish in the US. You'll see terms like COP, EER, and SEER. Those allow you to compare pretty easily. Currently the minimum is a SEER of 13, but I've seen units as high as 22 advertised.
Anytime there are multiple standards for manufacturers to choose from, customer confusion is guaranteed.
Half the article wasn't about a/c efficiency it was that HFC is more of a greenhouse gas than CO2, and was agreed to be phased out. Is there really an HFC replacement - what is it? I wasnt aware.
https://en.wikipedia.org/wiki/Montreal_Protocol
> It was agreed on 16 September 1987, and entered into force on 1 January 1989... As a result of the international agreement, the ozone hole in Antarctica is slowly recovering.[3] Climate projections indicate that the ozone layer will return to 1980 levels between 2050 and 2070.[4][5] Due to its widespread adoption and implementation it has been hailed as an example of exceptional international co-operation, with Kofi Annan quoted as saying that "perhaps the single most successful international agreement to date has been the Montreal Protocol".
Could higher efficiency cooling be done by using more evaporative cooling systems (Swamp Coolers)[0] rather than traditional AC units? There are climates where evaporative cooling is not effective, but perhaps they would be useful in the majority of climate regions. [0] https://en.wikipedia.org/wiki/Evaporative_cooler
Where they're effective I think people already tend to use them due to how cheap they are. The article mentions the regions that are starting to buy the most A/Cs are places like India and SE Asia, all of which are humid and hot.
American air conditioners running at full power, chilling the interior and dripping on the sidewalk below on a hot day always deeply trouble me. Maybe it's my european view on things, but for contrast here in Munich we aren't just building out a city-wide heat network, but we also have a cold network! Cold river water flows through the pipe network that traverses the city and large office building can get connected t…
Just insulate the houses in the US. I am always shocked how badly built US houses that cost 600k are.
That said, fiberglass insulation mostly only helps against convection cooling/heating. I.e. through the movement of air. Summertime heat is mostly conductive and radiative i.e. near infrared. Insulation doesn't do much to stop that.
Shade trees however help this big time. A large tree placed in the right spot to shade a house in the afternoon can replace as many as seven window air conditioner units.
Failing all of the above, stoicism isn't that bad, honest, neither are life style changes that shift high activity periods to later in the day, they are widely practised in Mediterranean countries.
American air conditioners running at full power, chilling the interior and dripping on the sidewalk below on a hot day always deeply trouble me. Maybe it's my european view on things, but for contrast here in Munich we aren't just building out a city-wide heat network, but we also have a cold network! Cold river water flows through the pipe network that traverses the city and large office building can get connected t…
what does that do to the river, fish, algae, waste processing, etc. If you ran say houston with river water how many degrees would it be?
I have a Fujitsu mini split that has been awesome in terms of bringing my electric bill down versus window units (we live in Maine, central A/C is less common here, and few homes were built with it until the 2000's). It does, like most splits, use R-410A, but I'd be happy to use something else if it didn't kill the efficiency. In parallel with refrigerants and efficiency, though, I wonder if the article misses on men…
I'd want to see the energy calculations for highly insulated, well sealed buildings. There is more material up front, but the insulation works during the heating season too.
Of the top of my head, a normal family house (150m2, 1-1/2 stories) is allowed to consume between 5000-6500 kWh per year (low number in southern Sweden, same as Denmark. High number northern Sweden above the polar circle).
This generally means >220mm insulation in walls and roof and >300mm insulation in the foundation. In northern Sweden you need a geothermal pump to hit those numbers.
People in the US consume way too much air conditioning. It's pretty common where I work for people to have sweaters to put on inside due to the AC. Outside it's in the 80ies, with something like 10% humidity in the summer - absolutely perfect unless you're doing hard labor in direct sunlight.