If you factor in cost of storage required to provide continuous power, then you get way more expensive and less reliable. Now this problem is solved by, surprise, fossil fuels. [0]

Ofcourse solar is cheaper when it is sunny, provider might even need to pay consumer to get them to consume. [1]

[0] https://www.forbes.com/sites/michaelshellenberger/2018/05/15...

[1] https://www.businessinsider.com/renewable-power-germany-nega...

Continuous aka base-load power is considered a defect as it's not load following. You can load follow with nuclear but then it becomes ridiculously expensive. France gets around this largely by buying and selling to other countries, but that does not scale.

Really, going 100% nuclear takes either massive over supply or large scale energy storage just like solar. Wind however can supplement solar while still costing less than nuclear and allowing you to more closely match the demand curve.

A little peaking power allows you to avoid significant grid storage at very reasonable costs, and as I said fix transportation etc.

PS: The need for grid electricity storage is overblown. Storing energy for more than 1 day means you very rarely use that stored energy making in non-viable. When you can have 2x as much solar and still only pay 4c/kwh that's pointless. Within the day it needs to compete with an over supply of energy most of the time.

We are comparing two energy sources: one where output depends on the weather, and can go to near 0 another where output is strictly predictable but takes time to change.

Option 2 have the problem of oversupply and undersupply. This forces either storage or fossil fuels in the picture.

Option 1, however, only deals with oversupply, which does not require expensive mitigations.

Not obvious why option 2 is preferable here

First, you can go off grid using 100% solar and a relatively small battery system as long as you get enough solar cells. The reason this works is your daytime input never drops to 0 and it's generally lower when you need less energy for AC systems.

In terms of the grid, Wind and solar really can't go to 0 over large areas. The minimum vs maximum output shows high variance, but maximum output is largely irrelevant. Really what you care about is minimum vs average output and that's more narrow band than you might think. Even better by locating Wind / Solar you can more closely match your daily demand curve.

Option 1, costs far more per kWh even if you can use every kWh, it's just get's worse from there. As it still needs over supply as power plants need occasional maintenance and the grid maximum and minimum demand over a year are wildly separated. You can setup maintenance around peak annual demands, but even then you will have occasional unexpected shutdowns.

Majority of energy consumption and population happens in cities / industry, so if we are talking significant co2 soonest, we should really focus on these.

For large consumers like these to go solar/wind, you will have to really over-provision solar/wind so that minimum possible power output is still enough. (Calm night, anyone?) This looks highly inefficient and tough to predict.

Whereas nuclear can and are already operating in load following mode routinely: [1]

[1] http://www.oecd-nea.org/nea-news/2011/29-2/nea-news-29-2-loa...

First, most city’s have a lot of space for solar and can easily import wind power. ~66w/m2 average over 24 hours is 66 MW per km^2 / the percentage covered in panels and really adds up.

Wind really can't be calm for long periods over large areas because large areas will always have temperatures differences.

It's like saying what if the sun does not rise tomorrow? If that's actually happening you have much bigger problems.

Load following nuclear power plants become even more expensive. Not a huge deal on nuclear subs, but a major issue for civilian infrastructure. Just like energy storage they simply increase the cost of energy above alternatives.

PS: Now if you could get nuclear without any form of subsides down to about 2.5c/kWh then running 24/7 or peaking power with average load's of around 30% down at around 8c/kWh then I would agree it had a major place. But, it's just no where near those numbers.

In northern climates in the winter, people use hundreds of thousands of BTU per day burning fossil fuels to heat their homes. Translated to electricity, that's 30+kwh per day with a huge portion of that during non peak solar and wind.

In order to solve the energy problem, you also have to solve the heating one... and wind / solar currently can't do that.

Solar hot water heaters are cheap and work very well for home heating outside the arctic circle.

In the US we mostly use them for pool heating, as anything else costs to much, but somehow they are ignored for other uses.

Solar water heaters are not cheap. 1 square meter of evacuated solar tubing with a storage tank is > 4k, before installation. That 1 m^2 will give you at most 500w of solar gain for 2-3 hours... in total maybe 5k BTU. That's a factor of 20 off relative to existing systems.

That's not what I am talking about. Bulk collectors for a single home are ~500$. Flat plates run $1,000 - $2,500 per home. Evacuated tubes cost more and collect less energy, but produce hotter water. https://modernize.com/home-ideas/34541/solar-water-heater-co...

1 square meter evacuated solar tubing is used for hot water systems not home heating. It's a question of output temperature, the warmer the water the less cost efficient and more costly the system. High end systems include a backup water heater which means you directly save 1k on a hot water heater.

Anyway, for home heating you don't need 'hot' water, a heat pump operating on even 60f water vs 0f or below air is very efficient. You can also pre heat cold water with a flat plate feed that into your normal water heater and again save a lot of energy.

PS: Also, many people pay 1,000-2000$ / year on home heating even with a well insulated house. These systems generally have payback period under 10 years, assuming you actually need significant amounts of heat.