[jahnu]

A very fair question and the answer is complicated. Production costs and transmission costs are separate. Also demand changes the market rate. And even if renewables are cheaper to produce in a market usually the highest price regardless of source sets the price. This is to incentivise the cheapest production methods to be invested in.

It’s a massive topic and I encourage everyone to go and dive into it. It’s endlessly fascinating and also one of the really positive stories in the world right now which can help balance your emotions in a sometimes depressing world. At least for me it does.

[bryanlarsen]

> This is to incentivise the cheapest production methods to be invested in.

It's also just a rule of economics. The price is set at the cost of the most expensive production necessary to meet demand.

So if solar could fulfill 100% of energy demand, price would be the cost of solar, and any other more expensive generation would either lose money, shut down or idle.

But if we shut down or idle those today we wouldn't have enough electricity, so the price rises until the more expensive plants can stay open and demand is met.

[zahlman]

... So then why isn't the solar to replace the more expensive plants getting built?

[Macha]

Because at the moment wind has been the winner in the Irish climate, especially when you look backwards long enough to account for the time scales over which energy buildouts occur. Renewables have grown to 40% of the overall supply, resulting in the most expensive plants (currently coal plants, and before that peat) closing. Solar is entering the market rapidly though, it grew from like 1% to 4% in the last 3 years. So I wouldn’t be surprised to see some gas plants closing in the next few years, given the more expensive options are now already gone

[bryanlarsen]

Snarky response deleted.

That rule is a rule of free markets. Electricity is not a free market, so it only partially applies. Texas is closer to a free market, and unsurprisingly it is adopting solar faster than most.

[Qwertious]

>Snarky response deleted.

We appreciate your restraint.

[Qwertious]

It is. But solar produces most around midday and then tapers off toward dawn/dusk, so it might supply 100% of demand at midday but only 10% around sunset.

If you build more solar it'll meet 100% of demand for a larger portion of the day, which is what we're doing.

[Spooky23]

Solar is best used to take care of peak summer demand. It’s not gonna displace coal plants which tend to make up base load.

[bryanlarsen]

Base generation is a cost optimization that's been irrelevant ever since peaking plants became cheaper to operate than continuous operation plants. Any grid that can handle peak loads can also handle base loads.

[belorn]

It is not that complicated. When the energy crisis in EU happened a few years ago, it demonstrated clearly that people and industry is willing to pay a years worth of energy bills for a single month to keep lights and machine operating. What this mean is that you could in concept give people free power for 11 months, and then increase electricity prices by 12x for the remaining month, and people would still pay it.

This also demonstrated through most countries in Europe that citizens will vote to have government that fix the energy market. Citizens do not want a free energy market that can raise prices to any degree, and its their tax money that fund grid stability.

This all mean that the cheapest form of producing energy do not result automatically in reduced energy costs for consumers and companies. The product that people pay for is not energy in a pure form, it is energy produced at a given time and given location. Make the energy free but the time and location expensive, and the total cost will still be expensive.

Transmission can help Ireland, but it can also hurt it by linking it to a larger market that can create a even higher demand spikes than exist in the current local grid. If the linked grid has locations which has higher energy costs than Ireland, then Ireland will subsidize those people by linking the markets together. Rules like highest price regardless of source sets the price, and higher amount of transmissions, also tend to result in more companies getting paid to maintain operations and thus more parties getting paid that is not linked to the marginal cost of producing energy.

[Spooky23]

It's really not. Energy grids are not designed for distributed generation. In my US state, that means billions of infrastructure investment.

The people using carbon to create forcing functions to transition to renewables conveniently forget to mention that. Which sucks, as solar in particular is almost a miracle product, but at this point my delivery charges to get electricity exceed the electricity supply by 10%. 20 years ago, delivery was 30% of supply.

My state, New York, decided it would be smart to turn off the nuclear plant that supplies 20% of NYC electricity, and replace it over a decade with a rube goldberg arrangement of gas, offshore wind, solar, and Canadian imports. The solar is hampered by distribution capacity, gas was slowed down by corruption and is being limited by environmental activists, we elected a president that believes that windmills give you cancer, and of course we are picking fights with Canada now.

[TheOtherHobbes]

Renewables run on competent government.

If you don't have competent government, that's not the fault of renewables.

This is not snark. With forward-looking rational planning the transition could have started decades ago, and we could have had a low carbon energy economy by 2010 at the latest.

But fossils make so much money they can buy the policy they want, and here we are arguing about national tactics instead of planetary strategy.