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Comment by CyberDildonics | Hacker News Reader

Hope their electricity isn't being generated with natural gas

This code would be about home appliances. But it turns out that massive generators are pretty efficient since they can operate at a huge scale. So even if the electricity replacing the gas stove was generated with gas, it'd still be better for the environment (and human health)

How does the efficiency of

* natural gas -> fire -> heat -> electricity in massive generator -> home -> induction stove -> pan

compare to

* natural gas -> fire -> heat -> pan

? And resistive is worse than induction.

I don't know if it's significant, but there is also energy to physically move the gas to your location, for the second scenario

Energy efficiency is going to be better with induction in that scenario since it only heats the food, not the pan, stovetop, etc. On top of that, the pollution is dramatically reduced. A modern natural gas turbine at a power plant is dramatically cleaner burning than an open flame in a kitchen stove.

> On top of that, the pollution is dramatically reduced. A modern natural gas turbine at a power plant is dramatically cleaner burning than an open flame in a kitchen stove.

Not to mention the pollution from the power plant is not going directly into your home (or face).

This is not a small or hypothetical impact. From the article:

> The air district estimated that the new rules for homes would cut nitrogen oxides enough to prevent 89 deaths per year in the Bay Area.

A lot of the heat of the flame doesn't end up in the pan.

Well, if you’re being fair you need to include how the gas GETS to the home.

You also need to compare:

  * natural gas -> home furnace -> fire -> warm air
   vs
  * natural gas -> fire -> heat -> electricity in massive generator -> home -> heat pump -> warm air

The latter is, surprisingly, something like 2x the efficiency because while large scale electricity generation from gas is only about 40% efficient, you can get a COP in the neighborhood of 5x on the heat pump.

The part that isn't obvious is that the fantastical-sounding "5x" isn't really about energy efficiency but rather about changing the problem from "generating heat" to "moving heat from one place to another".

The primary use of natural gas is heating and in moderate climates burning natural gas to heat your house is under half as efficient as burning natural gas at a power plant, moving the electricity to your house, and using a heat-pump to move the outdoors heat inside.

Making houses energy-agnostic seems like a big win if the cost is low and it can be, especially on new constructions. Plus if you assume that natural gas is bad then it should be obvious that thousands of houses directly depending on it is much worse than indirectly depending on it via the local plant. The local plant centralizes safety and pollution measures (e.g. no domestic gas leaks) and it allows a much quicker swapping of energy sources by the city when the time comes.

> The rules would essentially require all new residential construction to have electric water heaters by 2027 and heat pumps instead of furnaces by 2029.

By the time this is fully in effect for a significant number of people (i.e., basically the 2030s), yeah, the electricity will be pretty green. The target is 90% renewable electricity by 2035, and the mix was already around 34% renewable in 2021 statewide.

It seems fairly prudent to require new construction to use the super-green electricity instead of building infrastructure to burn more dinosaur juice.

This is about residential usages, not power generation, and after the San Bruno explosion killed eight people, I can see where they're coming from.

https://en.wikipedia.org/wiki/San_Bruno_pipeline_explosion

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