Humans have caused 1.5 °C of long-term global warming according to new estimates

Looking into the numbers a couple if months ago I was surprised how little it costs to stop climate change.

On the order of 100-200 trillion USD. Which is roughly 100-200% of global yearly GDP. Or 2-5% of yearly GDP until 2050. This could well be provided by printing money at all the federal reserve banks.

This investment will likely bring in a positive return on investment because it reduces the negative climate impacts.

Without such investments the downstream costs in climate change adaptation will be very expensive

There is also a good case to be made that the prices being bandied around are actually much too high [1]

TL;DR is three major factors:

1. The agencies that are doing the estimates are _very_ bad at exponential development curves (cough cough IEA estimating solar [2])

2. Unfortunately much of the developing world's economy is not growing as fast as we previously thought it would (similar thing happening with birthrates)

3. Many costs are absolute and _not_ marginal, which is just wrong IMO. We are going to need the energy either way, we should be talking about the "green premium" (as far as it exists), not how much it'll cost to generate XX TWH of energy

[1]: https://www.economist.com/interactive/briefing/2024/11/14/th...

[2]: https://www.economist.com/interactive/briefing/2024/11/14/th...

> Many costs are absolute and _not_ marginal

If you turn off your gas generator and replace it with solar + batteries, you will spend the entire cost of solar + batteries plus the decommissioning cost of gas (that may be negative if you can sell some parts) to go back to exactly the same point you were before.

So, no the cost is only marginal if you accept you will follow the depreciation curve of you infrastructure. And that's way too slow to reach the goal.

We have some crazy incentives to install new gas boilers in MA. I very specifically wanted to switch from gas to an air source heat pump and found there was only one company in the area who was willing to quote it (alongside their own, much cheaper, quote for a gas combi boiler) and their quote was outrageously non-competitive with local fossil fuel burning (in large part because our electricity is around $0.30/kWh, but also because they were the only supplier and even they didn't really want to do the work).

Even if the ASHP lasted forever, required no maintenance ever, and you had to buy a new gas boiler every 10 years, it would literally never make economic sense even if there weren't $2500 incentives on the gas boiler, but the movement on electric rates is definitely in the wrong direction if one wishes to displace natural gas with electricity (even at 400% efficiency).

Every year that things stay like this is pushing back the likely time to next re-evaluation for that property by another 20 years.

The price of home solar and batteries is dropping to the point that $0.30/kWh is becoming untenable in any home that has a decent amount of roof space. You’re better off financing a rooftop solar plant and buying 3-4 days of storage, even if you remain tied to the grid. Insofar as those costs are being driven by generation, the declining price of solar should eventually place an upper bound on what people will pay for electricity. Even if you don’t live in a sunny place and even if net metering pays $0, with a few days of storage you can reduce your grid consumption to the point where your actual need to consume expensive electricity becomes a tiny fraction of your overall usage. I think this will tend to push costs downwards.

Even for people who don’t have the space or capital to install their own solar, this will happen writ large as the US builds out utility scale solar, wind and storage.

Unfortunately, we have a 100 year old slate roof, which makes solar some mix of difficult, expensive, or not advised. At the exact moment of maximum heat demand (both seasonally and time of day), solar generation is at its lowest.

I do hope that slate lookalike solar tiles become advisable and cost-effective as I’d be happy to pay a small premium to generate and store locally.