Renewables supplied 71% of Portugal’s electricity in 2024, including 10% from solar, as production hit a record 36.7 TWh, according to grid operator Redes Energéticas Nacionais (REN).
Actually technology such as solar concentrators using molten salt is perfectly capable of supplying power at night.
In addition to that Portugal has also invested a lot in Wind generation (which, for all my criticism of my own country, was actually a wise bet) which doesn’t suffer from the problem of not producing at night or when there is heavy cloud cover.
Further, power consumption at night is mostly residential since industry seldom operates at those hours, and if electricity prices for business customers are made to float with availability, in a solar-heavy production environment big industrial consumers would be fitting their consumption to the period when solar is up.
Also, consider that even when the days are shorter in Portugal, they’re still longer than most of Europe because of how far South the country is compare to most of the rest - even at the peak of Winter days are at worst about 9h long.
As for that problem in drier years you pointed out, it’s even more of a problem with the hydro-heavy generation that the country has at the moment, so having more solar would make it less of a problem: yeah, drier years would affect the ability to store excess power produced by solar in dams but, guess what, solar would still be producing fine during the day even in the worst drought whilst hydro would not, same as it happened 2 years ago when the share of renewables was down to less than 50% exactly because a longuish period of drought forced most hydro-generation to stop.
Solar is hardly a silver bullet, but for a country like Portugal which has excellent conditions for it, solar should be a far larger slice of the generation makeup than it is, especially considering that the single biggest source of renewable energy - hydro - is the one which will be worst hit with the effects of Global Warming.
But yeah, your point is valid that renewables, at least in Portugal, won’t work by themselves unless there is some deeper interconnection with the rest of Europe and even Northern Africa to balance production across a wider area (when wind is not blowing somewhere, it still blows somewhere else, and the same applies to cloudy weather vs sunny weather), some kind of energy market which incentivizes heavy consumers to consumer the most when solar is at its peak and for investors to actually invest in energy storage to make money from “arbitraging the sunlight” (i.e. store cheap electricity during the day to sell it for more at night) or to use the kind of solar technology that also works during the night (i.e. molten salt solar concentrators). I say “at least in Portugal” because the whole problem with Global Warming and hydro-generation is going to be very nasty in Portugal (according to Global Warming models, which predict most of the country will basically turn into a desert) but some other places in Europe are going to be a lot more rainy and hence can reliably get their renewables from hydro.
That said, I am almost 100% certain that the politicians in Portugal will not make the right choices and instead will make the choices that maximize short-term profitability for the largest energy company in the country, because that’s mainly what they’ve been doing in the last couple of decades and they have a similar broad pattern of behavior of sacrificing the mid and long term for the short term (for example, the way housing has been handled in Portugal has caused a massive brain drain and further fall in birth rates in a country already suffering from an aged population, so in 10 or 20 years’ time there will be massive problems with things like pensions because the country will have too many old people, not enough young people and most of the younger won’t be the highly educated children of the locals but imported ones who generally have significantly less formal education hence less capability to work in high-value-added domains).
Actually technology such as solar concentrators using molten salt is perfectly capable of supplying power at night.
In addition to that Portugal has also invested a lot in Wind generation (which, for all my criticism of my own country, was actually a wise bet) which doesn’t suffer from the problem of not producing at night or when there is heavy cloud cover.
Further, power consumption at night is mostly residential since industry seldom operates at those hours, and if electricity prices for business customers are made to float with availability, in a solar-heavy production environment big industrial consumers would be fitting their consumption to the period when solar is up.
Also, consider that even when the days are shorter in Portugal, they’re still longer than most of Europe because of how far South the country is compare to most of the rest - even at the peak of Winter days are at worst about 9h long.
As for that problem in drier years you pointed out, it’s even more of a problem with the hydro-heavy generation that the country has at the moment, so having more solar would make it less of a problem: yeah, drier years would affect the ability to store excess power produced by solar in dams but, guess what, solar would still be producing fine during the day even in the worst drought whilst hydro would not, same as it happened 2 years ago when the share of renewables was down to less than 50% exactly because a longuish period of drought forced most hydro-generation to stop.
Solar is hardly a silver bullet, but for a country like Portugal which has excellent conditions for it, solar should be a far larger slice of the generation makeup than it is, especially considering that the single biggest source of renewable energy - hydro - is the one which will be worst hit with the effects of Global Warming.
But yeah, your point is valid that renewables, at least in Portugal, won’t work by themselves unless there is some deeper interconnection with the rest of Europe and even Northern Africa to balance production across a wider area (when wind is not blowing somewhere, it still blows somewhere else, and the same applies to cloudy weather vs sunny weather), some kind of energy market which incentivizes heavy consumers to consumer the most when solar is at its peak and for investors to actually invest in energy storage to make money from “arbitraging the sunlight” (i.e. store cheap electricity during the day to sell it for more at night) or to use the kind of solar technology that also works during the night (i.e. molten salt solar concentrators). I say “at least in Portugal” because the whole problem with Global Warming and hydro-generation is going to be very nasty in Portugal (according to Global Warming models, which predict most of the country will basically turn into a desert) but some other places in Europe are going to be a lot more rainy and hence can reliably get their renewables from hydro.
That said, I am almost 100% certain that the politicians in Portugal will not make the right choices and instead will make the choices that maximize short-term profitability for the largest energy company in the country, because that’s mainly what they’ve been doing in the last couple of decades and they have a similar broad pattern of behavior of sacrificing the mid and long term for the short term (for example, the way housing has been handled in Portugal has caused a massive brain drain and further fall in birth rates in a country already suffering from an aged population, so in 10 or 20 years’ time there will be massive problems with things like pensions because the country will have too many old people, not enough young people and most of the younger won’t be the highly educated children of the locals but imported ones who generally have significantly less formal education hence less capability to work in high-value-added domains).