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Comment by dragontamer | Hacker News Reader

> The long-term solution to this is to replace gas ovens with electric ones.

Not really. Burning natural gas turns 90%+ of its chemical energy into heat. Its incredibly efficient.

In contrast: turning natural gas into electricity wastes 60% of the chemical energy (only extracting ~40% of the chemical energy).

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Burning natural gas inside our homes is surprisingly efficient use of fossil fuels, far better than centralized electricity production. Its probably the last thing to replace on the list of electrification-technologies.

If all that cooking-electricity comes from a natural gas peaker plant, then you've just doubled your usage of natural gas.

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You're missing a few key factors that sway things in the favor of electric:

* Induction burners are much more efficient, as gas generally is wasted by heat wicking around the edge of your pan.

* There is a significant amount of natural gas that is lost (without being burned) via leaking out of pipes. I think the industry reports something like 3% is wasted. Given natural gas contains a lot of methane, that has a pretty large effect on greenhouse gas emissions. Removing gas lines to residences should, hopefully, reduce that amount since there are less pipes and joints running everywhere.

* As others have pointed out, power mix is usually not 100% natural gas. In terms of greenhouse gas creation, it's going to favor electric production, I think, based on the current mix of electricity in most places.

>as gas generally is wasted by heat wicking around the edge of your pan.

Not that we shouldn't be moving away from gas, but that heat might not be a waste in the wintertime, since it is also displacing heat you needed to keep your house warm. Of course it is best if to use a heat pump to keep your house warm, because you can then get efficiencies of greater than 100%.

Most of that heat is likely to be vented outside if you're using proper range hood ventilation. Also, it's a negative during the summer time when it's heating up the house. I know plenty of folks that dread using the oven or stovetop during the summer since your house gets so much hotter.

Overall, it seems like it's a net neutral in terms of heating unless you're in a climate that skews heavily one way or the other.

My two contentions with this line of reasoning is that

a) It doesn't consider the transfer of energy from the stove to the pot. Burning the gas may realease 90% of the chemical energy, but how much of that makes it into the pot.

> turning natural gas into electricity wastes 60% of the chemical energy.

There are plenty of other sources of electricity that are not natural gas.

> a) It doesn't consider the transfer of energy from the stove to the pot. Burning the gas may realease 90% of the chemical energy, but how much of that makes it into the pot.

Roughly the same as the inefficiencies of an electric stove.

I recognize that "induction stoves" have a different property, but the original poster said "electric", not "induction". Both electric, and gas, stoves, heat up the pot and the air around the food, causing inefficiencies. But these inefficiencies are roughly equivalent between electric and natural gas.

> There are plenty of other sources of electricity that are not natural gas.

None of which serve the same "peaker" purpose. Since none of the electric-ovens come with large-scale batteries to save power from ideal time periods, the most likely use of electricity will be the natural gas peaker plant that's been tasked with frequency-stabilization.

> the original poster said "electric", not "induction".

Induction stoves are electric. I meant to refer to both induction and conventional electric stoves.

.. induction and resistive-element electric hobs have drastically different efficiency profiles. They should be kept in different categories.

It's like comparing 2 stroke and 4 stroke gasoline engines.

> Roughly the same as the inefficiencies of an electric stove.

As someone who regularly cooks with both, this is quite clearly not the case. When I cook with a gas stove everything around the burner gets ridiculously hot, not just the pot, while on the glass top electric stove, the surrounding environment is comfortably cool.

Gas flames do not direct heat well.

> Roughly the same as the inefficiencies of an electric stove.

That does not seem believable at face value.

I will leave the electric vs induction to a side since we'd both be playing mind reading games if either of us argue one way or another.

> None of which serve the same "peaker" purpose.

I agree that none of the other options currently serve that purpose at the scale of natural gas. But the discussion is about long term solution.

>If all that cooking-electricity comes from a natural gas peaker plant, then you've just doubled your usage of natural gas.

I think the idea is to move away from that.

Regardless, even using natural gas power generation electric induction boiling comes ahead.

>Burning natural gas inside our homes is surprisingly efficient use of fossil fuels, far better than centralized electricity production.

This isn't true.

Technology Connections tested a typical electric range, an electric kettle, and a gas range, and calculated the Watt-hours needed to heat 1 liter of water using each.

He found that a gas burner required 375.8Wh and a plug-in electric heater used 190.4 Wh. Induction is even more efficient.

Even with transmission losses, burning the gas in a large, much more efficient central power plant and sending it in the form of electricity to the home where almost all of the energy gets transferred into the pot instead of the surrounding air as is the case with an open flame will result in much less gas being used to perform the same work.

https://www.youtube.com/watch?v=_yMMTVVJI4c

All of this ignores the myriad of other improvements induction heating has over gas like not polluting the inside air, being impossible to leave on accidentally after cooking, and not being an explosion risk due to gas leaks.

Sure, if your only source of electricity is fossil fuels like natural gas, then just burning them directly is better when heat is all you want. But if you have renewable sources of electricity, isn't that better than using fossil fuels at all even if it is technically less efficient?

Yeah, exactly. If everyone has gas stoves you need gas, if you have electric there can be more sources of energy, and to a certain extent electricity if fungible across multiple sources (if you have power plants).

> to a certain extent

Devil is in the details. Peaker plants are almost always natural gas, and I'd expect an electric oven (high power appliance that immediately turns on when you turn it on, and immediately turns off when turned off) is most likely using electricity from a peaker plant, rather than a baseload plant.

The peaker plant/base load choice is based on aggregate load though, the power provider has little to no knowledge of what appliances households are using. An electric stove, and realistically anything else that uses electricity, is therefore using one or the other based on the usage pattern of the whole customer base at that time.

> at that time.

Time is the more important thing here.

If you turn on your electric stove at 3pm, when the grid is stressed from the afternoon sun, your electricity is almost certainly coming from a peaker plant (unless you're in California, at which point the peaker-plants are coming on at 6pm or so).

If you turn on your electric stove at 2am in the middle of the night, the grid is almost not being used at all, and cheaper nuclear power / baseload plants are probably what powers your stove.

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Its not so much "The Grid has 30% renewable energy on the average". Its "At 2pm, the grid is mostly non-renewable due to the number of peaker plants" and "at 2am the grid is mostly renewable nuclear"

As solar panels get deployed, the times will change, but the concept won't change. Peaker plants are the only plants that can respond to consumers. Anyone using electricity at times outside of what renewable energies can provide will effectively be using natural gas.

>If you turn on your electric stove at 3pm, when the grid is stressed from the afternoon sun, your electricity is almost certainly coming from a peaker plant (unless you're in California, at which point the peaker-plants are coming on at 6pm or so).

For California, you can check the actual generation mix:

https://www.caiso.com/TodaysOutlook/Pages/supply.html

For today:

                | MW @ 2AM | MW @ 3PM
    ------------+----------+---------
    Renewables  |   5337   | 17228
    Natural Gas |  10339   |  9568
    Hydro       |   1529   |  1178
    Imports     |   6216   |   778
    Batteries   |    -23   |   183
    Nuclear     |   2241   |  2240
    Coal        |      7   |     2

...so at 3PM ~31% of your electricity was produced by natural gas, and at 2AM ~40% of your power was produced by natural gas.

>> (unless you're in California, at which point the peaker-plants are coming on at 6pm or so).

California has a lot of solar panels.

The natural gas peakers come on at 6pm as the sun sets, but the day is still hot so AC is on.

At 6pm (1800) today, its reporting:

* 8983 Renewables

* 11933 Nat Gas

* 3403 Hydro

* 5948 Imports

* 1351 Batteries

* 2235 Nuclear

* 1 Coal

Won't grid-scale batteries replace natural gas peaker plants in the long term?

That appears to be the plan/long term sustainable grid scale storage of some sort.

There’s also the potential for demand smoothing.

> turning natural gas into electricity wastes 60% of the chemical energy (only extracting ~40% of the chemical energy)

Modern combined cycle gas turbines are ~60% efficient:

https://www.ge.com/power/transform/article.transform.article...

And if you can co-locate some process that needs low-grade heat, you can also use the waste heat.

The electricity can come in a variety of other ways, doesn’t have to be just burning natural gas.

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