Great graphs thanks. The monthly correlations of wind with demand are interesting, especially for future heat. Very large stores of hot water linked to heat networks have a lot to offer Northern latitudes. (though ultimately underground storage of coolth may prove more essential for human survivability in the South) Adding a street heat network may enable existing power connections to be used with ASHPs etc to INPUT heat into a network for transfer to central mass thermal storage for use later. Online webinar in English: https://topsectorenergie.nl/nl/kennisbank/webinarreeks-warmteopslag/
IRENA has some thermal storage publications.
Should we make price differences bigger to stimulate thermal storage investment and the use of electricity instead of oil and gas combustion fuels?
e.g. Stop adding fixed levies and taxes onto retail kWh prices, perhaps removing them one week, doubling them the next?? To stimulate Demand Side and long duration thermal storage Investment?
I am a big fan of thermal storage in general (and heat networks). I think that we should remove fixed levies: taxes to be proportional (like VAT) and network charges to be based on capacity mostly and maybe even dynamic as well.
Currently, fixed charges especially on the distribution level are generally reducing a lot the attractivity to consume flexibly, including for heat/cold storage.
It's not only Europe that's too small for geographical dispersion to be of much help in alleviating solar intermittency, but any continent. Of the three factors that determine PV production at any given moment (time of day, season, cloud cover) only the last is random so that correlation will be high and positive between places at similar latitude and longitude, such as Spain and Germany in your example, even if cloudiness is uncorrelated: astronomy trumps meteorology as far as solar is concerned.
Any meaningful gains from dispersion would require transmitting power across multiple time zones, which is unlikely to be economically viable, even if there is no ocean in the way.
This is of course not the case for wind as your analysis clearly shows. Excess production of wind power is more likely to find a market in neighboring regions than excess PV production: It’s summer and noon everywhere at (almost) the same time on our continent.
I’m a keen reader of your posts and do agree that numerical analysis like yours’ are important to start to understand the issue at hand. Nevertheless, is it not correct to say that intra-day solar output is 0 for more than 50% of the time greatly reducing whatever solar/wind correlation you might find at larger timescales? One can argue that on a yearly scale countries like Spain might already have, or are close to having, all the solar/wind capacity installed required to potentially cover yearly demand, but that doesn’t solve the 24 hour cycle. I’m coming from my own small personal experience as I built a 100% off-grid house on the Mediterranean coast of Spain which went live back in the summer of 2020. I was surprised after a full year to find out that I had to rely on my backup gas generator (sounds familiar?) much more often than the “models” predicted. I’m traveling now but if you’re interested I can give you all the details about the installation, production and demand, as well as how much more PV and battery capacity I had to install just to achieve the objective of 98% independence.
Hi lsgv, this sounds very interesting! I am currently tinkering on a similar project for a private residence. If you'd be willing to share your data, that would be very much appreciated! yurivanengelshoven[at]gmail[dot]com.
Thanks for your interest. As said before I’m out traveling for the moment with little time to develop this but you can find an intro, albeit superseded by newer developments, on this link
Hello again. I don't know if you had the opportunity of going through the intro about my installation in the HA forum. In short, 100% off-grid, and we produce everything ourselves including water (large garden irrigation, pool, domestic usage) and waste management. As it is not possible to add images to posts I wrote a short note on my experience which you can access here.
1. Based on these correlations, what duration storage (hrs, days, weeks, etc) do you think is most beneficial to economically integrate solar/wind into the grid? Say, to 40% of electricity mix while maintaining relatively low prices.
1. Very difficult to answer. It depends on many factors and especially on the considered country/region. If you have large hydro for the remaining 60%, then you might not need any storage (or maybe just hourly). If you are a flat country with high demand during winter, you might need some serious seasonal storage. Also, if storage costs are high, you might overbuild renewables and curtail instead of storing. That are just a few considerations but there are many others, so difficult to provide a definite answer.
2. Another difficult question ;-).
Point 1: we are still very much at the early stage. A new technology requiring substantial capital and infrastructure is generally built over decades, not years. So, it is not for tomorrow.
Point2: it also all depends on the definition of the green. I posted on the green grid exception in the EU. The three criteria (temporal correlation, geographical correlation, and additionality) lead to increased costs. So, if you are more "laxist", you can produce green H2 that is not a bit less green but less costly. Not sure that we will have the same international definition by the way.
Point 3: it will depend very much on the technology development and associated costs. I am not sure that we could realize the same gains with electrolyzers than solar.
Point 4: Better direct electrification than hydrogen, in general.
I probably forgot other points but thanks for your questions.
1. Totally understand that it’s kind of an impossible question, was more just looking to understand how you’d think about it so your answer was helpful!
Great graphs thanks. The monthly correlations of wind with demand are interesting, especially for future heat. Very large stores of hot water linked to heat networks have a lot to offer Northern latitudes. (though ultimately underground storage of coolth may prove more essential for human survivability in the South) Adding a street heat network may enable existing power connections to be used with ASHPs etc to INPUT heat into a network for transfer to central mass thermal storage for use later. Online webinar in English: https://topsectorenergie.nl/nl/kennisbank/webinarreeks-warmteopslag/
IRENA has some thermal storage publications.
Should we make price differences bigger to stimulate thermal storage investment and the use of electricity instead of oil and gas combustion fuels?
e.g. Stop adding fixed levies and taxes onto retail kWh prices, perhaps removing them one week, doubling them the next?? To stimulate Demand Side and long duration thermal storage Investment?
@AndyFrewX
I am a big fan of thermal storage in general (and heat networks). I think that we should remove fixed levies: taxes to be proportional (like VAT) and network charges to be based on capacity mostly and maybe even dynamic as well.
Currently, fixed charges especially on the distribution level are generally reducing a lot the attractivity to consume flexibly, including for heat/cold storage.
It's not only Europe that's too small for geographical dispersion to be of much help in alleviating solar intermittency, but any continent. Of the three factors that determine PV production at any given moment (time of day, season, cloud cover) only the last is random so that correlation will be high and positive between places at similar latitude and longitude, such as Spain and Germany in your example, even if cloudiness is uncorrelated: astronomy trumps meteorology as far as solar is concerned.
Any meaningful gains from dispersion would require transmitting power across multiple time zones, which is unlikely to be economically viable, even if there is no ocean in the way.
This is of course not the case for wind as your analysis clearly shows. Excess production of wind power is more likely to find a market in neighboring regions than excess PV production: It’s summer and noon everywhere at (almost) the same time on our continent.
Interesting analysis.
I like how you incorporate both geography and different time scales. Both are often missing in analyses of solar and wind.
I’m a keen reader of your posts and do agree that numerical analysis like yours’ are important to start to understand the issue at hand. Nevertheless, is it not correct to say that intra-day solar output is 0 for more than 50% of the time greatly reducing whatever solar/wind correlation you might find at larger timescales? One can argue that on a yearly scale countries like Spain might already have, or are close to having, all the solar/wind capacity installed required to potentially cover yearly demand, but that doesn’t solve the 24 hour cycle. I’m coming from my own small personal experience as I built a 100% off-grid house on the Mediterranean coast of Spain which went live back in the summer of 2020. I was surprised after a full year to find out that I had to rely on my backup gas generator (sounds familiar?) much more often than the “models” predicted. I’m traveling now but if you’re interested I can give you all the details about the installation, production and demand, as well as how much more PV and battery capacity I had to install just to achieve the objective of 98% independence.
Hi lsgv, this sounds very interesting! I am currently tinkering on a similar project for a private residence. If you'd be willing to share your data, that would be very much appreciated! yurivanengelshoven[at]gmail[dot]com.
Thanks for your interest. As said before I’m out traveling for the moment with little time to develop this but you can find an intro, albeit superseded by newer developments, on this link
https://community.home-assistant.io/t/victron-fronius-off-grid-pv-energy-dashboard-mqtt-and-modbus-integration/392450
It gives you the basis of the whole system architecture and initial requirements. I’ll write about the development when I’m back in a few days.
Thanks a lot and enjoy your travels!
Thanks for your comment. Yes, please, send me an email directly when you have time. It looks very interesting.
Hello again. I don't know if you had the opportunity of going through the intro about my installation in the HA forum. In short, 100% off-grid, and we produce everything ourselves including water (large garden irrigation, pool, domestic usage) and waste management. As it is not possible to add images to posts I wrote a short note on my experience which you can access here.
https://www.dropbox.com/scl/fi/ztsghoeab66e8e8d0zmry/Case-study-PV.pdf?rlkey=7ss9lz9uha06axbz3uc5ihexc&dl=0
Hope this is clear and happy to clarify any open points.
Two questions:
1. Based on these correlations, what duration storage (hrs, days, weeks, etc) do you think is most beneficial to economically integrate solar/wind into the grid? Say, to 40% of electricity mix while maintaining relatively low prices.
2. What are your strong views on green hydrogen?
Thanks for your questions.
1. Very difficult to answer. It depends on many factors and especially on the considered country/region. If you have large hydro for the remaining 60%, then you might not need any storage (or maybe just hourly). If you are a flat country with high demand during winter, you might need some serious seasonal storage. Also, if storage costs are high, you might overbuild renewables and curtail instead of storing. That are just a few considerations but there are many others, so difficult to provide a definite answer.
2. Another difficult question ;-).
Point 1: we are still very much at the early stage. A new technology requiring substantial capital and infrastructure is generally built over decades, not years. So, it is not for tomorrow.
Point2: it also all depends on the definition of the green. I posted on the green grid exception in the EU. The three criteria (temporal correlation, geographical correlation, and additionality) lead to increased costs. So, if you are more "laxist", you can produce green H2 that is not a bit less green but less costly. Not sure that we will have the same international definition by the way.
Point 3: it will depend very much on the technology development and associated costs. I am not sure that we could realize the same gains with electrolyzers than solar.
Point 4: Better direct electrification than hydrogen, in general.
I probably forgot other points but thanks for your questions.
Thanks!!
1. Totally understand that it’s kind of an impossible question, was more just looking to understand how you’d think about it so your answer was helpful!
2. Thanks!