You think that it is not right when people use LCOE to compare solar and nuclear?

You are right. But you should extend the reasoning behind that to all aspects

The core reason is the time-varying nature of the electricity value.

Let's explore 🧵

1/11 Historically, the electricity value was quite constant. When you burn stuff, the cost is relatively flat. See here for a random week in Germany 2017. For days, the hourly price does not vary more than 5 €/MWh

(but it crashed already in the weekend as we burned less)

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/1/The rise of large-scale batteries.

If you are in the power sector, large-scale batteries are set to change grid operations, as their ramp rates are extremely high.

They will cover all power reserve needs in the coming years.

Let's discuss in a 🧵

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1 Batteries are coming, fast, in large quantities and bigger.

Here, is a project for 600 MW in Belgium (4-hour storage).

2/6

I love the hydrogen ladder from @MLiebreich. If you do not know it, please have a look.

I think that besides the first line and probably steel + chem. feedstock, hydrogen will simply not be used (at least in my career and I am 35).

Let's discuss one: Long-term storage 🧵
1/8 Long-term storage for electricity is our ability to save some energy in one month and give it back a few months later.

Often forgotten, we do already have that in Europe. It is called hydro with reservoirs. Collectively we can store around 2 weeks worth of consumption.

2/8

Right in time for spring ;-)

605 MW: what could be the impact of such project on capture rate for solar?

Let's calculate together

1/5

pv-magazine.com/2024/04/10/eur… Using this formula:

605 MW : around 600 GWh, 0.12% of market share gained.

Capture rate to decrease by 0.00468.

Capture rate in 2023 was 0.756, so, it will impact it by 0.62%.

2/5

https://twitter.com/LionHirth/status/1691347083687546881

Rooftop solar in Germany is going to have a massive impact on electricity markets.

It is expected that close to 96 GW of solar will be installed.

And this is rooftop solar is very inflexible.

1/5 It is inflexible because you will receive a fixed amount independent of the markt price. From 6 to 13 c€/kWh, depending on the size and if you auto-consume or not.

2/5

Th most challenging part of a decarbonized grid will be to manage the total energy (both surplus and deficit) on a weekly and monthly level.

Hourly and even daily variations will be challenging but we have the solutions. A short thread 🧵

1/10 Wind and solar have great potential for combination. There are many factors but more or less, they have some complementarity (see here for Germany 2023).

2/10

The rise of vertical solar.

Why I think that it is coming. A small explanation.

1/5 First, The capture value of solar is higher when it is not in the middle of the day.

Here for Germany in 2023.

Market value is sometimes even negative in some hours

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How much money should you deserve to make with solar on your roof?

We are often praising the incredible rise of solar, including rooftop solar but the way they got paid matter a lot for the homeowner and the electricity system.

Let's delve into that if you may. 🧵

1/13 First, net metering.

Often, people with little knowledge of the electricity world would think that net metering is simply logical.

It is not. It implies taking the grid as an infinite battery. And bye bye network costs.

2/13

Increasing the flexibility in our electricity systems by incentivizing people to consume when power is produced. Everybody agrees.

But practically, are we really serious about it?

We might be but unfortunately, we are also supporting measures to go against flexibility.

1/10 It is probably a consensus amongst the energy world that we need to push consumers to react to market prices (= consume when there is sun and wind, or too much nuclear).

This is clear when you consider residual load (load - wind - solar).

2/10

Electricity is key to decarbonize. All models show that lowering emissions will go together with increased use of electricity (heating, transportation)

Yet, we sometimes miss what is important in the value of electricity: its constant availability in time and location.

1/10 LCOE is still relatively widespread for comparing electricity sources.

Yes, solar and wind have lower LCOE but this is far from being the full story.

2/10

In 2023, there were 3 days with negative prices below -100 €/MWh: 28 May, 29 May, and 2 July

The very negative prices were always achieved during the solar peak (here DE)

The solar curve is almost perfect, with no reduction in output.

A 🧵on the absence of incentives.

1/10 This might well become more and more problematic as Germany, and the EU, are engaging in a rapid increase of solar (2 to 3 more than currently).

DE: 215 GW by 2030.
EU: 750 GW by 2030 (600 GWac) RepowerEU.



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https://twitter.com/JomauxJulien/status/1763208249342402849

A thread 🧵 for all the French Nuclear lovers. An analysis of French nuclear prod. and electricity prices + comparison with Germany. Anno 2023.

One case is one day.

We see the evolution from winter to summer.

We also see some weekend modulation.

1/6 The weekend modulation does not mean that we use more of something else.

Indeed, this is the coverage of the load by nuclear in %. We observe that the weekend is actually more covered by nuclear than weekdays.

2/6

Rooftop solar and utility-scale solar: why does the difference matter?

Quick thread on their impact on electricity prices and grid operations. 🧵

1/9 In general, rooftop solar (especially on residential units) is "install and forget". There is no incentive for active management based on elec. prices/grid operations

To illustrate that, in Germany, you still get up to 130 €/MWh (even for hours when price is 0 or negative)

2/9

The arrival of the duck curve across Europe.

A thread with various graphs 🧵

1. Huge expansion foreseen: 576 GWdc in 2027 according to @SolarPowerEU ...average load is only 308 GW in 2023! 2. So, we see that we burn not much fossil fuels when the sun is shining.

That's the graph from @EmberClimate on fossil fuel penetration in the electricity mix. Clear impact from solar (and less than 250 GWdc in 2023!)

6.7 TW for 2030 is a very impressive figure already.

At 15% capacity factor, it would mean 8800 TWh, which is 34.5% of global electricity consumption in 2022 or 27% in 2030 assuming 3% growth of electricity consumption every year.

What are the consequences? 🧵

1/5

https://twitter.com/solar_chase/status/1759858449913979024

If you have a capacity factor of 15% and the share of electricity from solar is 27%, it means that you have quite a few hours with 100% of the load covered by solar only.

This is what I believe would be the main barrier for solar (see my post on that).

2/5

Some more thoughts on the correlation between wind and solar, using different timescales. And with a link to market prices

It is a complex matter...

I use only data from Germany 2023.

First: monthly output. Nice complementarity. And bonus because a bit more in Winter.

1/11 OK, but this complementarity is valid for the current mix of wind and solar.

Wind is unfortunately losing momentum, while solar is booming.

For a 50/50% mix (1 MWh wind/1 MWh solar), we start to see less complementarity, especially since we need more in winter (in DE!)

2/11

European tour of the duck curves. It is coming in every country.

Here I plotted for various countries the normalized day-ahead prices. Normalization is done with a comparison to the yearly average.

1. Germany 2. France. Even with low penetration of solar, you see the same effect.

Why is solar going to be so disruptive?

Here are some reasons and reflections 🧵

First, Solar is the fastest (and still going faster). But wait, that's in energy. Since solar has the lowest capacity factor, in terms of power, it is even much faster.

1/7 Because it is growing so fast, planning has not kept up. Here is the capacity foreseen for 2030/2040 by the European transmission system operators in 2018.

Some scenarios have solar capacity that we will reach in 2 years.

A new line takes +10 years from planning to end.

2/7

Power reserves (or ancillary services) are a key component of our power systems.

I make here a (long) thread on the prices for ensuring the capacity of these reserves in Europe (Germany).

As always, there is a link with solar!

1/10 In Europe, we have different reserves with different characteristics. For most of them, there is a market-based approach. In a nutshell :

1) Fast: FCR - symmetrical reserves.
2) Slower: aFRR - one reserve upward, one downwards.
3) Even slower: mFRR (also up and down)

2/10

Nordics have a great advantage for their power grids: they possess (extremely) large energy storage.

The number 1 is Norway as the country can store 75.7 TWh in its water dams for electricity. That's 14 MWh per capita (a PowerWall has 1000 less energy).

1/6 Sweden has also very important water reserves, with 28.8 TWh (max value, of course, never fully used), or 2.7 MWh per capita.

2/6

Green hydrogen production in Europe, the conditions, and the somehow surprising exception of the "green grid".

Let's review 🧵.

First, green H2 = production of H2 with electrolysis using green energy.

The problem? We have to define what is green.

1/11 Green means that three conditions must be fulfilled.

1. Additionality (=must be new renewables).
2. Temporal correlation (=must be renewables on an hourly basis).
3. Locational correlation (=must be same bidding zone).

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