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A near 100% renewables grid is well within reach, and with little storage

reneweconomy.com.au

301–310 of 365 posts

Re: A near 100% renewables grid is well within reach, and with little storage

#301

Earlier quoted context omitted.

Cloud doesn't mean solar stops working - the decrease is 30-60% depending on thickness, but there's still very meaningful generation.

it also creates another problem - solar generation drop off very quickly when the sun is obscured. going from 100% to 10% or 20% in many cases. Where doe the power come from during these swings? What generation source can ramp up and down at that speed?

The grid is always managed such that any single plant or transmission line can trip at any time without causing voltage or frequency collapse. Clouds going over your solar farm is like the plant tripping but not as bad.

Re: A near 100% renewables grid is well within reach, and with little storage

#302

Earlier quoted context omitted.

The US also has plentiful natural resources vs. population size. It seems that Europe would be the least naturally blessed considering high per capita energy use and less solar resources. China has a high population to support, but also owns all that renewables manuring capacity. Other countries do not have such large and energy intense populations.

I feel Europe situation is by far better than here in Japan. Here, land is small, 75% of land is mountains (so hard to bring wind parts), suitable sea (shallower) for cheaper offshore wind is rare than it looks, much area heavily snows, grid is smaller and divided for 50/60Hz, and almost zero natural resources exists. Even if HVDC connection to foreign grid is possible solution, closer bigger lands (China and Russia)…

Floating solar (inland) and floating wind (at sea) are the answer. But Japan actually has a unique advantage in aiming for net-zero in that they have a culture of renewing buildings on short timescales and cenralised property ownership. They can reduce electricity demand and GHG emissions faster in the next decade by building better homes and offices than in rolling out renewables, though they can do both at the same time, and sticking building integrated PV on the new buildings is probably worth doing as well.

Re: A near 100% renewables grid is well within reach, and with little storage

#303
post #228

Earlier quoted context omitted.

Energy prices everywhere are up. That is what happens when the global economy is bouncing back from a pandemic and one of the biggest energy suppliers in the world decides to embark on the first major land war in Europe in over 70 years.

With the energy industry making record profits [1], my naive self has extreme trouble believing that's the whole story. https://energycommerce.house.gov/newsroom/press-releases/pal...

Why do you think that people who sell a commodity that has increased demand wouldn't make more money?

There's no need for a conspiracy. The people who make money from the gas extracted and exported from Australia will profit at the expense of the average Australian who pays more for the gas extracted from under their own soil. You could vote to have them distribute the windfall profits to the people, if they didn't have such a stranglehold on your politicians.

https://www.reuters.com/business/energy/australias-east-coas...

This is the same as many historical famines, where people starved to death while the crops grown in the same country were exported and sold overseas because rich, non-starving people can pay more than poor starving farmers. Banning or limiting exports might have helped in a roundabout way, but just not intentionally letting poor people starve to death would have been a simpler policy to implement.

Re: A near 100% renewables grid is well within reach, and with little storage

#304
post #115

Earlier quoted context omitted.

Swapping hydro from 24/7 power to a backup for wind and solar goes a long way to eliminate the need for storage. We don’t need more total kWh per year of hydro we need to be able to more flexibility get those kWh.

I’m not sure that’s true. Electricity generation is pretty regional, so it’s not like we can use a region’s hydro capacity to store energy for other regions. It can store energy for the region that already has hydro, but that region already has hydro so it probably needs less storage in the first place?

New York just approved $5 billion to import Canadian Hydro. This is already done on various smaller scales in the US and across the globe. People in Norway are being riled up by their right wing parties because they are selling hydro electricity (and gas) at a high profit to the rest of Europe via connections because of the Russian situation, and there's nothing the right-wing hates more than market-based price signals that suggest you should maybe use less fossil fuels and be more efficient.

Re: A near 100% renewables grid is well within reach, and with little storage

#305

Earlier quoted context omitted.

The effect of a lot of renewables can be the opposite, though. When the wind is blowing, all consumers may want to charge their Tesla's at the same time, meaning that the grid wil experience even more spikey load patterns. Batteries as part of the central grid can help, of course.

It seems that it can be easily adjustable by include grid capacity for pricing calculation.

It can, but that would lead to wasted energy when demand is pushed below supply (when there is no way to store the supply).

That sort of defeats the benefit of elasticity in the demand that was the premise. The idea was that when there is a lot of power being generated on a sunny and windy day, everyone should charge all batteries, heat their water a few extra degrees, run heating or air conditioning a bit harder, etc, as an hour later, the sun could go down, the wind stop blowing and power generation could be scarce.

On the other hand elastic supply sources with a fuel cost (hydro, fossil fuels and to some extent nuclear) are much more suited for cases where consumption elasticity is linked to limitations of the distribution systems.

Re: A near 100% renewables grid is well within reach, and with little storage

#306

Earlier quoted context omitted.

The effect of a lot of renewables can be the opposite, though. When the wind is blowing, all consumers may want to charge their Tesla's at the same time, meaning that the grid wil experience even more spikey load patterns. Batteries as part of the central grid can help, of course.

More spikes are good, it's the height of the tallest spike that determines the cost, so reducing that specific spike is the key. And one way to do that, is to spike at other times instead. Think about it like roads and rush hour. The width of the road is set for rush hour, and most of the rest of the time it's empty. Any way of shifting demand away from that peak is good. You'd have to shift an infeasible amount to c…

When I said "more spikey", I meant generally bigger spikes overall. The frequency of spikes is less relevant and not even very related. It is perfectly possible to have BOTH much higher maximum spikes AND greater numbers of relatively tall spikes. (For instance if you compare energy produced by a set of windmill farm to that produced by a group of nuclear plants.)

Re: A near 100% renewables grid is well within reach, and with little storage

#307

Earlier quoted context omitted.

More spikes are good, it's the height of the tallest spike that determines the cost, so reducing that specific spike is the key. And one way to do that, is to spike at other times instead. Think about it like roads and rush hour. The width of the road is set for rush hour, and most of the rest of the time it's empty. Any way of shifting demand away from that peak is good. You'd have to shift an infeasible amount to c…

When I said "more spikey", I meant generally bigger spikes overall. The frequency of spikes is less relevant and not even very related. It is perfectly possible to have BOTH much higher maximum spikes AND greater numbers of relatively tall spikes. (For instance if you compare energy produced by a set of windmill farm to that produced by a group of nuclear plants.)

If you mean higher annual peaks, then it's probably easier to say that, because that's exactly what has been motivating the early solar deployments and the early battery deployments.

The very high summer peaks correlate well with solar (in many places) and so shaving that peak saves you more than you were spending on solar, even before the price plummeted. Same with batteries replacing expensive gas peaker plants.

Overall demand is predicted to rise a little with electrification, but demand was falling in many places anyway, so between that and the tech above for shaving peaks, it's not really a problem.

Note it's a common thing for "pro-fossil fuel" advocates to show "peaks" without enough context. Usually what looks like a peak on a daily basis is in fact a drop in the bucket compared with the yearly peak.

The famous 'duck curve' is a good example of this, where solar and wind reduced the daily and yearly peak, and then the new lower peak in spring/autumn was pointed at as a "problem".

https://en.wikipedia.org/wiki/Duck_curve

> One misconception related to the duck curve is that solar photovoltaic power does not help supply peak demand and therefore cannot replace other power plants. In California, solar output is low at 7 pm when daily demand usually peaks.[20] This fact leads some to believe that solar power cannot reduce the need for other power plants, as they will still be needed at 7 pm when solar power output is low. However, California's annual demand peaks usually occur around 3 pm to 5 pm,[21] when solar power output is still substantial.[20] The reason that California's annual peak tends to be earlier than the daily peak is that California's annual peak usually occurs on hot days with large air conditioning loads, which tend to run more during midday.[22] As a result, solar power does in fact help supply peak demand and therefore can substitute for other sources of power.

Re: A near 100% renewables grid is well within reach, and with little storage

#308
post #239
post #62

Earlier quoted context omitted.

Australia is ~4,000km wide, so ~6% - totally manageable if it is needed.

Curious to know the relative costs of HVAC vs battery per megawatt/hour offset from peak solar production. 4000 KMs east to west is about 2.4 hours offset geographically. Would it be cheaper to have 2.4 hours of storage closer to the east coast of Australia, with solar farms close to the consumption? Or would building a 4000km HVAC transmission line from the west coast of Australia to the east coast be cheaper? I'd i…

The controversial conclusion I came to many years ago was all of the above ... I remember when the solar lobby was fighting the wind lobby fighting the hydro lobby to be the one true green energy source. It was and still is entirely pointless.

Distributed independent microgrids with interconnects fed by a range of power generation methods and size the generation at >1.5x power needs. Refurbish and maintain fossil fuel to fill when needed, and ideally make them as modular as possible with turbine halls being convertable between different fuel types.

Re: A near 100% renewables grid is well within reach, and with little storage

#309
post #282

Earlier quoted context omitted.

This is completely in line with reasonable priors: https://www.wartsila.com/energy/towards-100-renewable-energy... It's more of a science/engineering communication effort, because there's a lot of unreasonable priors out there. edit: also the 6.6GW of 'other' the current model uses, is the current actual gas plant size, not an amount that they predict as optimal or desirable. Similar with the Hydro, they used the cur…

On my reading of it, "Other" is the gap between the other modelled sources and the actual demand.

I may be mixing up his comment about limiting the Hydro to the current max output rate.

But, I believe they chose the levels on solar and wind to aim for, precisely because they knew 'other' would come in around this level, because it would be a poor demonstration of the viability of renewables otherwise. But they were at the mercy of the unpredictable weather and demand, so couldn't control it exactly, just much better than many people would assume.

Re: A near 100% renewables grid is well within reach, and with little storage

#310

Earlier quoted context omitted.

When I said "more spikey", I meant generally bigger spikes overall. The frequency of spikes is less relevant and not even very related. It is perfectly possible to have BOTH much higher maximum spikes AND greater numbers of relatively tall spikes. (For instance if you compare energy produced by a set of windmill farm to that produced by a group of nuclear plants.)

If you mean higher annual peaks, then it's probably easier to say that, because that's exactly what has been motivating the early solar deployments and the early battery deployments. The very high summer peaks correlate well with solar (in many places) and so shaving that peak saves you more than you were spending on solar, even before the price plummeted. Same with batteries replacing expensive gas peaker plants. Ov…

> Note it's a common thing for "pro-fossil fuel" advocates to show "peaks" without enough context. Usually what looks like a peak on a daily basis is in fact a drop in the bucket compared with the yearly peak.

I'm not pro-fossil, rather the opposite. I'm anti-fossil (GHG in general) fuel, and want us to use all production methods available that allow us to gut GHG emissions, including solar, wind AND nuclear. Eventually (a few hundred years from now, maybe, but eventually) it seems like fusion will be the final source.

Also, I'm concerned with replacing ALL sources of fossil fuels, including for heating, most industrial use. And for that to come true, I think we need to have a razor sharp focus on price to make it happen. Lately, even before the current crisis, it seems that prices have been going in the wrong direction while global GHG emissions continue their sharp increase.

It seems to me that part of the reason is that many "renewable" proponents are much more more happy to burn a lot of natural gas than to allow nuclear power, and that they're employing a variety of measures to make nuclear seem unattractive, even compared to natural gas. (I've seen some of these messages sponsored by oil companies, some of which seem to want to build expensive offshore wind parks close to where they already have oil platforms.)

I'm getting the impression that some costs of wind power, in particular, is being covered over. And I'm particularly thinking of wind power. This involves both the unstable demand, unavailability of storage and things like increased transportation costs not clearly linked to the type of source.

So, basically, what I'm looking for is ways to make ALL of solar, wind and nuclear as cheap as possible, with reasonable (and shared) safety and environmental standards.

For that to happen, honesty about real costs, accurate prediction models and willingness to remove factors that increase prices unnecessarily (often due to special interest groups) need to be investigated.

For now, my impression is that the real LCOE, including transportation, of nuclear could be A LOT lower than what is represented by new European and American plants, both based on historical prices and efforts in Korea and China, while the real LCOE of wind tends to increase sharply when wind power gets to about 20-30% of total energy production.

For now, my opinion is that we should continue to invest in solar and wind at the same rate we're currently doing while ALSO work on adjust regulation and the business climate for nuclear to allow the cost to come down at least to Korean levels. Meanwhile, all fossil fuel sources should be taxed at a high enough level to make sure both nuclear and renewable investments have a chance of being profitable (The tax should at least be brought up enough to cover the negative externalities of fossil fuels).

If such taxes were made federal (in the US) and collected by the EU (in the EU market), instead of being collected by individual states, one could at least set up the right incentives.

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