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Comment by acdha | Hacker News Reader

Two challenges: building AC systems are often surprisingly poorly designed and installed, especially if your building has ever had internal redesigns, so you’re picking which areas are either too hot or cold rather than getting the entire place the same temperature. Developers tend not to be high-status enough to get the building set for them — that tends to be the suit-wearing executive suite or, at many places, sales.

The other factor to consider is that people who are too cold can layer up but someone who’s too hot doesn’t have an option other than working from home.

One thing which increased environmental concerns is leading to is reconsidering both of these given how expensive AC is. Getting people to dress appropriately for the season would lead to a big reduction in peak electrical load in much of the U.S. In some cities like San Diego where distribution capacity is constrained that’s the difference between having brownouts or not.

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AC is the reason why I think solar power can do wonders even if it's nowhere near being able to meet all the demand.

Especially in dry climates like the American southwest, solar produces the most energy during the exact same hours when air conditioners need the most power. Build an excess of solar capacity, and you can probably prevent all brownouts. This would be a major benefit even for people who don't care about climate change.

I would expect the solar peak to be an hour or two earlier than the peak of AC demand.

It's not a perfect alignment but it's close enough: the key point is that you can generate the power without long-distance distribution requirements (which is a source of waste in the current model) with a considerable comfort margin.

In the example I mentioned, San Diego has (IIRC) three long-distance interconnects and building more is extremely difficult because the routes are generally full of homeowners who will sue you. You don't need to power every AC unit in San Diego completely off of solar the entire day — just enough to keep the total draw well below the capacity limits of that network avoids the prospect of brownouts or blackouts, and it would cut the number of times they have to pay industrial customers to reduce usage for a few hours.

You can turn the panels slightly to the west or fiddle with other angles if you're concerned more about aligning peak hours than producing the maximum amount of energy possible.

> The other factor to consider is that people who are too cold can layer up but someone who’s too hot doesn’t have an option other than working from home.

While true in the abstract, the real reason why most office buildings are "cold" is because indoor climate regulations are based on empirical thermal comfort models that were developed in the 1960s, and thus mostly based on the metabolic rates of men instead of women.

https://www.nature.com/articles/nclimate2741

I very much doubt that the people responsible for temperature control are aware of the empirical thermal comfort models from 1960. My prediction is that almost none of them have any idea that the study exist or what it says.

I contrast I suspect those people to be fully aware of the cost of running the temperature control system and if the CEO/manager of the company want it to be right now warmer or colder in their room. The resulting temperature is then the balance between costs and the willingness to make the CEO/manager happy.

That's basically the same point from a different angle: most set-points were created to be comfortable for men in suits, in an era where business attire was a requirement for office-workers in most fields.

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