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Comment by math_dandy | Hacker News Reader

In much of Western Canada, energy use is highest at night in deepest winter when there is no appreciable wind, meaning that the grid is completely reliant on gas-fired power. If we want to reduce gas-fired capacity, we need another source of on-demand power. Meaning either nuclear or a robust storage solution. There seems to be more enthusiasm for the latter, but there’s no buzz about any viable solutions on the horizon.

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Nuclear isn’t great for ‘peaker’/infrequent usage. The large up front capital costs means they require running at 90%+ utilization to be economic, and the way the radioactive decay chains work means they tend to take awhile (hours) to stabilize at their high power outputs, and hours to days to ramp down in actual effective power. Even a scrammed ‘hot’ reactor takes half a day to a couple days for daughter products to burn down to the point it doesn’t produce significant thermal power (hundred of megawatts to even half a gigawatt thermal).

That’s what got Fukushima btw - when they shut the reactor down and then the backup generators got destroyed, they lost their ability to pump water to cool the reactor (which requires significant electrical power), which proceeded to start to melt down the core, and causing massive hydrogen buildup, eventually blowing up the reactor building.

Some new designs allow more effective emergency passive cooling, but the issue remains - nuclear plants are great for baseline power, but they aren’t good for sub-day, hourly, or finer grained peaks. Both economically and technically. Think ‘fully loaded container ship’ or ‘multi-mile long train’.

Pumped storage, battery, or fossil fueled turbines are great for those faster reactions - and often can provide useful sub-second grid stability too. Think ‘speed boat’ or ‘passenger car’.

Nuclear is terrible for peak loads of course but absolutely perfect for base loads. We should be producing something like 60% of the base load with stable and emission free nuclear, then all kinds of renewables can provide the rest. When there is excess power we charge batteries, pump hydro or make green hydrogen for use in peaks.

For the amount Canada recently spent on the expanding the Trans-Mountain Pipeline ($30 billion) we could probably build a nice nuclear plant.

It depens on the fuel mixture. Some fuel mixtures are more suited for load following operation that base load operation.

The economic argument against nuclear for peaking remains, however.

Wind power produces more at night. See eg here for an explanation: https://www.reddit.com/r/askscience/comments/10mvxm4/comment...

I totally believe that this is true on average. But there are a few weeks in the January/February when we're sitting under a high pressure system with clear skies, no wind, and -30C temperatures. Power generation needs to be able to handle annual extremes, not just averages.

According to https://www150.statcan.gc.ca/t1/tbl1/en/tv.action?pid=251000... January and February are among the most productive wind energy months in Canada, with the summer months being notably lower. I couldn't easily find stats about nr of low-wind days. I guess Canada also has the advantage that it's a big country so local weather variations doesn't necessarily matter as much.

Hydrogen is a solution for seasonal leveling at high latitude (and for Dunkelflauten.)

I'm absolutely not an authority in these matters, and any corrections are welcome and appreciated.)

From what I've read, "green" hydrogen made from electrolysis with energy from non-carbon-emitting sources extremely energy intensive, as is compressing it for transport. Transport is also expensive. To my knowledge, there aren't any pipelines in Western Canada that could transport it, so I guess it's trucks and train cars. But maybe there's potential there because hydrogen wouldn't need to be the backbone of the grid, it would just need to pick up the (substantial?) slack when renewables weren't producing.

Seasonal leveling doesn't require transport -- make the hydrogen above the storage caverns.

Green hydrogen certainly is more expensive than hydrogen derived from fossil fuels, but if we are imagining a 100% RE grid, that hydrogen isn't available. It does make sense to burn natural gas directly instead of burning green hydrogen as long as the CO2 charge isn't high enough to rule out use of natural gas. This is why we're not yet seeing a large green hydrogen role out in Europe.

The interesting question is whether fossil hydrogen with CO2 sequestration is acceptable. It may be preferable to green hydrogen, depending on things like methane leakage.

An alternative solution to hydrogen could be methane synthesis from captured CO2 and green hydrogen. The infrastructure to transport, store and use methane (aka 'natural gas') is already there.

This is possible, although the problem is the cost of capturing the CO2. It might be better to synthesize a liquid fuel; methanol is probably the easiest. Capturing the CO2 of combustion is probably easier than capturing atmospheric CO2, so that should be included. Overall, the RTE will be lower than hydrogen, but maybe it's cheaper if the geology doesn't favor hydrogen storage.

Another possible alternative would be artificial geothermal, with very high temperature rock at fairly shallow depth. Obviously that's not transportable.

I can’t understand why, with winters known to be how they are, there is no district heating. If that infrastructure had been in place, a transition to carbon-less sources of heat could be well underway.

Canada is very dispersed/low density in many areas. Think ‘US if it wasn’t so crowded’, outside of a few cities close to the US border.

For Edmonton & Calgary at least, which house the majority of Alberta’s population, such infrastructure would’ve meant better planning for growth, reducing the low-density sprawl we see today.

Only if one knew what it would end up looking like - and it would have looked like that if everything had been done differently getting here.

Canada doesn't invest in infrastructure until it's too late. And by then, it's too late.

Are there no rains in western Canada? Why is hydro not an alternative?

Where I’m at (Saskatchewan) everything is very flat. We have some hydro but all of the “economically viable” hydro resources have been tapped. I worked out the math once on doing pumped hydro storage and the best siting I came up with involved building a massive reservoir in the middle of one of the most beautiful provincial parks we have and putting the downstream low point 80km away.

There’s a really interesting nomenclature thing in Canada with respect to electricity. Every province (except Alberta) has a government-owned power company. If you want to tell whether or not a given province has good water resources for generating electricity you just need to look at the name of their power company: BC Hydro, Manitoba Hydro, Ontario Hydro, Quebec Hydro… all good places for hydroelectricity. SaskPower? Not so much.

We have recently bought into the SMR idea and one of the questions I used to have was “why the hell didn’t we build nuclear 20 years ago here”. The problem, I understand now, is overall grid sizing. You don’t want to have a single power plant that provides more than about 10% of your grid capacity. In SK, our total generation capacity is around 3500MW; a conventional 1+GW reactor would have dramatically exceeded the 10% cutoff. Smaller 300MW reactors provide a much better fit for our grid.

Even if hydro is a viable option, it's still terrible for the environment.

No rain in winter, the snow won’t melt until much later.

Same is true here in Sweden, we just have deep enough reservoirs. We also have nuclear, but hydro is also a really big part and as Canada has even lower population density than we do it shouldn't be unreasonable. But perhaps terrain in many areas isn't helpful.

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