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Comment by coldpie | Hacker News Reader

> I'm confused. Who has agreed that solar+wind is off the table?

Ah okay! That's our disconnect. Do go run the numbers on how much natural gas we're burning up here. It's a lot, like seriously a lot. How many batteries will we need to ensure that amount of energy is available for (say) 2 weeks of continuous cloud cover at -10 ~ -40 degrees F? Keep in mind that if it fails, people will die. I don't feel confident enough in my own analysis to share it, but do try it out yourself for an exercise. It's pretty eye-opening.

> Yet while there are plenty of simulations of doing full grids with only solar, wind and batteries

I would love to see this! Can you share some? Do they account for converting Minnesota's heating needs from natural gas?

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You're again talking about simulating only Minnesota I suspect. If you want a realistic simulation there are others in the thread and RethinkX has had a whole-US simulation for a long time. What I've never seen is a nuclear roll-out simulation that argues that's a good option. Do you have one of those?

> What I've never seen is a nuclear roll-out simulation that argues that's a good option. Do you have one of those?

I don't know what a "nuclear roll-out simulation" is, exactly. As stated earlier, my position is that we should be building both nuclear and renewables. We should build whatever makes sense for the area in question. If renewable+storage can solve all of an area's needs, then that's fantastic and we should absolutely do that.

If I understand right, you are arguing we should not be building any nuclear, even in Minnesota. I'm unconvinced that renewables+storage alone can solve the Minnesota winter problem. I'm asking if you can provide a link to an analysis showing that we can feasibly and cost-effectively solve the Minnesota winter problem without any nuclear power. Can you please link to one?

> I don't know what a "nuclear roll-out simulation" is, exactly.

Any simulation where building nuclear power plants makes economic sense would do.

> I'm unconvinced that renewables+storage alone can solve the Minnesota winter problem.

You're again asking for simulations about Minnesota specifically which doesn't make sense. Unless you're thinking of seceding from the union and closing the borders to energy trade, as long as the US as a whole can do it Minnesota in particular can be a net energy importer in winter if that's what's needed. Here's the RethinkX simulation of that:

https://www.tonyseba.com/wp-content/uploads/2020/11/Rethinki...

"Our analysis makes severely constraining assumptions, and by extrapolating our results from California, Texas, and New England to the entire country we find that the continental United States as a whole could achieve 100% clean electricity from solar PV, onshore wind power, and lithium-ion batteries by 2030 for a capital investment of less than $2 trillion, with an average system electricity cost nationwide of under 3 cents per kilowatt-hour if 50% or more of the system’s super power is utilized."

This is almost 5 years old at this point. Others have linked other such analysis. At this point asking people to show them simulations for renewables while trying to argue for nuclear is disingenuous. Renewables are the ones being built out at scale all over the world while nuclear struggles to deliver new projects and doesn't seem to have a viable path to being cheap.

> You're again asking for simulations about Minnesota specifically which doesn't make sense.

No I'm not, I have no idea how you are getting that idea. I'm asking for an analysis showing that Minnesota's winter needs can be met without building nuclear plants. That's it. You can solve that problem in any way you like, including importing power from other states and nations.

> Here's the RethinkX simulation of that

Thanks for the link. I focused on the New England scenario, as it's the most similar to Minnesota of the 3 scenarios. It doesn't seem to account for heating. This is the problem I keep coming to in these analyses. See page 25:

> Our model takes as inputs each region’s historical hourly electricity demand ... For the New England region, our analysis applies to the ISO New England (ISO-NE) service area which provides 100% of grid-scale electricity generation for the states of Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont.

Our heating is not supplied by electricity. I definitely believe that our current electricity demand may be met by renewables in a feasible timescale, but that leaves out the massive hole of heating our buildings.

The only reference I could find to New England's heating is this little note at the bottom of page 46:

> If New England chose to invest in an additional 20% in its 100% SWB system, for example, then the super power output could be used to replace most fossil fuel use in the residential and road transportation sectors combined (assuming electrification of vehicles and heating).

But I don't see any actual numerical analysis backing this up. Given their analysis earlier only spoke about electricity usage, I'm not super convinced by this one sentence.

Additionally, the New England scenario suggests they need 1,232 GWh of storage to supply only 89 hours of electricity for the area. Even if we agree that's a sufficient amount of time, the currently largest energy storage facility on the planet is only 3 GWh[1]. We would need 410 such facilities for New England alone. Can we really scale battery tech up that much, especially given resource constraints like Lithium and copper? Maybe! Hopefully! But it's a big question. Meanwhile, nuclear is here now, and it works. I don't think we should be betting our future on unproven tech.

[1] https://electrek.co/2023/08/03/worlds-largest-battery-storag...

> No I'm not, I have no idea how you are getting that idea. I'm asking for an analysis showing that Minnesota's winter needs can be met without building nuclear plants. That's it. You can solve that problem in any way you like, including importing power from other states and nations.

If that's your assumption then this is a non issue. Minnesota is currently less than 2% of total winter electricity demand in the US. Lets be pessimistic and assume that because it needs more heating in winter than average those 2% become 5% with electrification of heating nationwide. Even if 100% of that electricity needed to be imported from other states that's still a very small amount of the total. You could import all that solar and wind energy from other states if you can't produce any at all locally. The scenario is obviously much better than that, you'd only need to cover the shortfall which is what already naturally happens in joint grids all over the world.

> Meanwhile, nuclear is here now, and it works. I don't think we should be betting our future on unproven tech.

I'm still waiting for a link that shows that nuclear can be built at anything approaching reasonable cost. In all these discussions that's always presented as a given and then all the discussion is on the shortfalls of renewables. Meanwhile the actual reality on the ground is that the renewable roll-out is rising exponentially and nuclear projects are practically non existant.

Please double-check my math here. Minnesota delivers about 70,000 million cubic feet of natural gas to customers in the coldest months[1]. 70,000,000,000 cf of NG is about 72,730,000,000,000 BTUs[2]. That's equivalent to 21,315 GWh[3] of energy created by NG per month. Divide that by 31 days and you're looking at 687 GWh of natural gas per day or 29 GW of continuous generation. Minnesota's current entire electricity generation capacity is 17 GW[4], so we're looking at roughly tripling our current capacity. Nearby states are about on the same order, so we would be sucking down a whole lot of their power during low-generation periods. If we want to prepare for 7 days of no electricity generation, we would need 4,809 GWh of energy storage solely for heating, which is about 1600 instances of the currently largest battery-storage system on the planet, just for heating Minnesota.

Some combination of nuclear and solar/wind feels much more realistic to me to meet this demand, than building out that many batteries.

This is all napkin-math-y, so feel free to fudge it up and down a bit. But I just can't get the numbers to feel reasonable to me.

[1] https://www.eia.gov/dnav/ng/hist/n3060mn2m.htm

[2] 1 cf ng = 1039 btu https://www.nrg.com/resources/energy-tools/energy-conversion...

[3] https://www.convertunits.com/from/British+thermal+unit/to/gi...

[4] https://en.wikipedia.org/wiki/List_of_power_stations_in_Minn...

You've now ignored the simulations others have done, after insisting on those repeatedly, and have started making your own to again conclude solar and wind must not be viable and nuclear necessary. Meanwhile I'm still waiting on any kind of study that says nuclear can be built at anything approaching a viable cost. This is not a reasonable way to discuss something.

Fair enough, agree to disagree. I do want to say thanks for engaging me on this, and for digging up that study link. This was the most productive conversation I've had about the topic on HN.

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