"Downshifting" would mean going back at least two hundred years in most technology if you want to avoid catastrophic climate change without "new" feats of technology like renewable electricity and batteries. Most likely that would ensue also going back about 200 years in the population Earth can sustain. Recall that we're now about 6 billion people more than in the early decades of the 19th century.

if you talk about preserving energy, reducing consumption and using social and cultural means to reduce the impact on the planet these days you're pretty much immediately labeled as some kind of anti-growth luddite, in particular by the 'green tech' crowd, looking at Ramez Naam among others.

VC's, 'entrepreneurs' and green energy journalism seems to have a vested interest to in a sense consume 'green innovation' rather than just treating it as technology.

I don't have problems with people advocating reducing consumption to reduce the impact on the planet. Personally I think it's about as effective as telling people to not watch porn but you do you and advocate away. It's harmless.

I do have problems with people who argue against transitioning to 100% renewable energy with this argument. That's actively harmful. You won't actually convince anyone but it plays into the hands of anti-EV, pro fossil fuel interests. The likes of BP that spill a fuck ton of oil into the ocean and we just shrug it off. And then they go "but mining lithium is harmful" (which it isn't, at least not more harmful than mining gigatons of coal or fracking gas).

The problem with your position is a total lack of perspective of what's harmful to the planet and what can realistically be done about it.

>The problem with your position is a total lack of perspective of what's harmful to the planet and what can realistically be done about it.

The heaviest polluters and carbon emitters on earth could very easily reduce their pollution and emissions by at least 50% say, if not way more by changing the way we consume, travel, what we eat and so on. We are talking low hanging fruits here.

Do you now how many battery stations we need to plaster on earth, how many not yet invented technologies we need to get to significant renewable use which we could get for free if we could turn half of our coal plants off?

Just for 'perspective', over the last 30 years we have gone from, 93-95% carbon based fuel sources to... 88% today. People want to go to Mars in 10 years but it's 'unrealistic' to advocate that people replace beef with chicken and air travel with a train? This is the actual most bizarre thing about this argument, the complete inversion of who has lost perspective and realism.

> Do you now how many battery stations we need to plaster on earth?

Global power consumption is at ~23TWh. To make it through the night on nothing but solar, you'd need about 1/3th of that dedicated to batteries (Likely a lot less though due to wind, hydro, and nuclear production) So ~8 TWh of storage on the extreme end. Roughly 8000x our current battery deployments.

A lot, but not really crazy.

> how many not yet invented technologies we need to get to significant renewable

0. There are no technologies needed for significant renewable deployment. About the only thing needed is manufacturing capacity. Solar efficiency is crazy high as is wind which has driven cost/watt way down. Battery prices have similarly fallen off a cliff (and are still falling), which makes that extremely feasible at this point.

New tech will make the whole transition cheaper, but certainly isn't needed to get things switched over.

> which we could get for free if we could turn half of our coal plants off?

Ok.. but that solves only the power generation problem and runs smack dab into the politics problem. Wanting to turn off coal doesn't make it happen.

> 'unrealistic' to advocate that people replace beef with chicken and air travel with a train?

Yes, because you are talking about winning over a huge diverse group of people. Going to mars requires one rich asshole to invest in mars travel. He doesn't have to convince millions to change their habits or minds.

Realism is realizing that you can't control others thoughts or behaviors. An excellent example of this is what's happening with COVID.

You want to tell me it's realistic to convince people to give up their favorite foods when getting people to just wear masks is seen as a breach of liberty or whatever garbage?

Come on. The amount of rational people is FAR too low to realistically expect that sort of pleading to work.

>The heaviest polluters and carbon emitters on earth could very easily reduce their pollution and emissions by at least 50% say, if not way more by changing the way we consume, travel, what we eat and so on

Then how are batteries going to screw that up? If and when we do that, using batteries would still make things more energy efficient and greener.

>The heaviest polluters and carbon emitters on earth could very easily reduce their pollution and emissions by at least 50% say, if not way more by changing the way we consume, travel, what we eat and so on. We are talking low hanging fruits here.

Very easily? People start protests over much less than 50%.

The problem is that many forum-commentators don't know how to craft policy that avoids figuratively trying to "boil the ocean".

It is a sort of Nimbyism. Tail pipe emmisions are low for EVs since they have no tail pipe.

ICEs running on renewable fuel has localy observable emissions and are not sexy. The decommision of ICEs are way easier then EVs and the refeuling infrastructure simpler for liquids. It is a shame there is a look-in on EVs.

Even if the power source is pure coal, EVs are still significantly better than ICE cars when it comes to air pollution per distance travelled, as well as carbon footprint per distance travelled.

Except most power grids are not pure coal, they include some mix of zero carbon energy already. And there are opportunities for EVs to contribute to a high-renewables grid with smarter charging.

And separate to your concern (or lack thereof) about climate and renewables, moving emissions away from the tailpipe has significant advantages for local air quality where most people live.

> ... carbon footprint ...

I was referring to renewable fuel, where the tailpipe carbon goes back into nature.

> moving emissions away from the tailpipe has significant advantages for local air quality where most people live.

Yes, but where most people don't live is also where ICEs are advantageous in that an BEV would need Tesla size batteries for range, which are oversized for normal city-ish driving.

ICEs running on renewables need a lot more renewables. An EV turns something like 80-90% of the power a wind turbine produces into movement. If you want to use synfuels in an ICE you lose >>50% just by turning the electricity into fuel and then the ICE only turns 30% of that into movement.

Playing devil's advocate, the parent comment didn't mention "synfuels" at all, it mentioned "renewable fuel", which includes things like sugarcane alcohol, which is very common here in Brazil as a car fuel; many cars come out of the factory with flex fuel engines which can run on either gasoline or alcohol, and every fueling station I've ever seen always has at least one pump for alcohol.

That is of course a good point. You can make small amounts of those from agricultural waste. If demand outstrips supply from waste though, the area you need to farm to drive a couple of miles is really large. I didn't do the math, but I wouldn't be surprised if you got more energy out of agricultural waste if you turn it into electricity+heat in a biogas setup.

How much of the power of the wind does the turbine turn into electrical power? It is not really a fair comparison.

I think BEVs are a better solution for most cases, but my feeling is that renewable ICEs and EVs with smaller batteries and "trolley bus" solutions just are way downplayed and underrated.

I don't understand what you want to say. The comparison between BEVs and ICEs running on synfuels starts at the point where you want to turn electricity into motion. BEVs are more efficient by a factor of around 6. The efficiency of the wind turbine doesn't matter. You'll need six times as many of them if you want to burn synfuels instead of driving a BEV.

Is that true for e.g. ethanol too? I mean sure, it is true for H2-gas made with electricity but when making ethanol you are starting with lower grade energy.

Ethanol is made from wood or grain and any losses during the harvesting etc for the end product is comparable to the wind losses around the turbine (note that it is a bad comparison, since wasting wind is kind of no cost ...) or comparable with burning wood to power a steam machine generator to power EVs.

I.e. the degenerate case is using gasoline do power a powerplant to power a EV. You would be better off just using it in an ICE car. My point is turning wood into ethanol might be a good supplement to solar and wind EVs. E.g. for wood ethanol 1J product requires 0.6J input (except the wood of course) [1].

https://afdc.energy.gov/fuels/ethanol_fuel_basics.html https://ilsr.org/wp-content/uploads/files/ethanolnetenergy.p... (table 1)

Biofuels don't scale very well. You can indeed produce some "for free" from waste, but once you start planting areas solely for producing biomass to turn into biofuels, you're environmentally much better off to leave the land to nature and put up some PV or wind turbines there.

But yes, a tiny sliver of fuel demand can be satisfied from plants. You're right about that. I'm less convinced that you're better off burning the fuel in an ICE than turning it into electricity in a large power plant and running an EV. Large generators are more efficient than small ones. If you manage to do something useful with the waste heat of your power plant (e.g. use it for district heating), there is no way a small ICE can compete, even if you take into account transmission and charging losses.

In general I agree, but lets do some napkin math:

UK 9.34 million hectares agriculture area. [1] 6,470 l/ha ethanol in Brazil [2]

60,4 billion liter ethanol for all agricultural land in the UK. (Surely a big share of the land is not good for this usage but what ever.)

About 45 billion liter of gasoline and diesel used in UK per year.[3]

I mean, it is not totally off by orders of magnitude to be practical for a significant share of driving.

[1] https://en.wikipedia.org/wiki/Agriculture_in_the_United_King... [2] http://www.globalbioenergy.org/uploads/media/0907_Goldemberg... [3] https://www.racfoundation.org/data/volume-petrol-diesel-cons...

Well, most of that land is already used to produce food. I'm not so sure whether it would be a good idea to start up serious competition to food production.