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by solarkraft 1479 days ago
> with far less wasted energy

Small nit-pick: Electricity generation itself is often very lossy. In the case of fossil sources, the energy waste is just further up the chain (with solar power too, but it matters much less).

2 comments

A generator powering the grid for the electric company is going to capture a far greater portion of the fossil fuel energy than the gas range in your kitchen. There will be some loss transmitting electrical power from the generator to your house, but usually less loss proportionally than than energy wasted above a gas range. As you suggest, climate-neutral renewable sources make up a tiny portion of most power grids, but that will likely change in the coming years.
This is the same reason that EVs still win on overall efficiency, even if your electrical supply is fossil fuel based. You get to take advantages of efficiency in scale.
It’s probably pretty close to a wash. A gas stove is about 40% efficient.

A good combined cycle has power plant is about 60%, transmission is about 90%, and an induction stove is about 85%. That gives a net efficiency of 46%.

So that's better if you're sourced by gas, and _way_ better if you're sourced by a renewable method? Looking at the national grid [0] in the UK, 40% of our energy came from gas, and most of the rest is renewable energy or nuclear. That significantly swings in favour of electric kettles.

[0] https://grid.iamkate.com/

Well you have to consider the margin. If you change out your gas stove, where is the extra bit of electricity going to come from? Probably gas, although they may build some more renewable if enough people switch.

A gas stove is one of the last things that should be converted, because heat is the most efficient use of fossil fuels.

In general, any conversion of heat energy to mechanical or electrical energy will have a fairly low efficiency, so switching an energy source in a way that adds such a conversion will have at best a small benefit.

On the other hand, switching from a gas to an electric car requires an extra heat->mechanical conversion step at the power plant, but it removes a heat->mechanical conversion step in the car, so in general this is a favorable trade.

You can also get a favorable trade in home heating if you replace a gas furnace with an electric heat pump, or a gas water heater with a heat pump water heater, because the heat pump can get effectively well over 100% efficiency.

> the energy waste is just further up the chain

Just because both are "lossy" that does not mean at all the losses are of comparable magnitude.

So, actual question: "You need X amount of gas in a power plant to generate enough energy for 1000 households to heat their water with induction" vs "You need Y amount for the same number of households using gas stoves". What is the ratio between X and Y? You claim it is about 1. Is it? Or much larger than 1 or much smaller than 1?