4 ms·

I get what you are saying but that is not quite how it works. The marginal price may be determined by gas, but my electricity in the south island is mostly hyd

I get what you are saying but that is not quite how it works. The marginal price may be determined by gas, but my electricity in the south island is mostly hydro. Right now as I write this comment, the grid in the south island is being powered by hydro and wind. Less power is currently being exported north than is being generated right now by gas up North. So if I turn on a heater, it does not mean that an extra couple of kw of gas is being turned on in Auckland. Right now the total power accross the country is 84% renewable. So worst case if I use a heater it is 16% not renewable. In any case, electric water heaters in nz are ripple controlled and only heat at the lowest demand. So any electric water is using as much hydro as possible.

robocat 7y ago
> So worst case if I use a heater it is 16% not renewable. As a choice as an individual: The heater is off. You turn it on. The extra demand you added usually comes 100% from gas generation. > In any case, electric water heaters in nz are ripple controlled and only heat at the lowest demand. So any electric water is using as much hydro as possible. Our lakes are like batteries. If you choose to take an extra long hot shower powered by hydro at the moment, but 3 months later the lakes get low (because there is not enough rainfall) then extra gas generation is used 3 months later which matches 100% of your extra power usage due to your hot shower choice. Reducing your power usage works similarly, in that you save gas generation. As an individual, your choices 100% affect how much gas is used, because we are assuming others make no change. This is the key to thinking about marginal usage. Marginal economics are critical to understand when running a business too, since it is similarly confusing (and we all naturally make simple mistakes when thinking about it). There are times when your extra usage comes only from hydro, but it is usually not simple to know at the point when you are adding power usage. Reducing power usage can only ever help, so different.

robocat 7y ago

> So worst case if I use a heater it is 16% not renewable. As a choice as an individual: The heater is off. You turn it on. The extra demand you added usually comes 100% from gas generation. > In any case, electric water heaters in nz are ripple controlled and only heat at the lowest demand. So any electric water is using as much hydro as possible. Our lakes are like batteries. If you choose to take an extra long hot shower powered by hydro at the moment, but 3 months later the lakes get low (because there is not enough rainfall) then extra gas generation is used 3 months later which matches 100% of your extra power usage due to your hot shower choice. Reducing your power usage works similarly, in that you save gas generation. As an individual, your choices 100% affect how much gas is used, because we are assuming others make no change. This is the key to thinking about marginal usage. Marginal economics are critical to understand when running a business too, since it is similarly confusing (and we all naturally make simple mistakes when thinking about it). There are times when your extra usage comes only from hydro, but it is usually not simple to know at the point when you are adding power usage. Reducing power usage can only ever help, so different.