[bit_logic]

They're focusing on transportation fuel (cars and airplanes), but another area of great potential is power generation. The current trend is to build solar/wind and replace coal with natural gas plants as a stop-gap until some grid-scale energy storage is ready. Everyone assumes that energy storage will be batteries.

But what if the natural gas plants don't have to be a stop gap? Just keep building more and more solar/wind, as much as the land can handle (imagine most of the desert in California converted to solar). Who cares if generation greatly exceeds daily demand. Use all the excess solar/wind to create fuel for the natural gas plants. There's already a vast infrastructure and experienced workforce to do this. Use the fuel during the evening and put any excess fuel into storage, there's so much existing ways to store fuel. Then use that during winter when solar generation decreases.

We need to stop thinking carbon fuel = fossil fuel and so carbon fuel = bad. Carbon fuel is simply a form of energy storage, a kind of "battery".

[galaxyLogic]

> imagine most of the desert in California converted to solar

I would start making a regulation that says all parking-lots MUST have a light-weight roof on top of them on top of which are solar panels.

Imagine all (outside) parking lots having solar-panel covered roofs.

This would be easy to enforce in regulatory terms, which regulating all of deserts is not. You want to have a parking lot? You must have solar panels as well. And it could double as a charging station.

[MichaelCollins]

I think you'd crush any brick-and-mortar business smaller than Walmart like that.

[Schroedingersat]

The business or land owner doesn't have to pay for it. Just let whoever put the panels up provided they provide x watts to charge cars. Even extremely cheap land is starting to show up as a significant portion of a solar install.

Store owner wins because covered parking. Panel owner wins because the increased logistics are offset by free land.

[gwd]

> The business or land owner doesn't have to pay for it. Just let whoever put the panels up provided they provide x watts to charge cars.

Which sort of begs the question, why isn't this already a thing? Why aren't there companies going to businesses which own parking lots and saying, "Let me lease the air above your parking lot. I'll install and maintain the frames and the solar panels, manage the connection to the grid, the whole lot; I'll pay you $x per meter per month, and your customers have shade."

[l1tany11]

I think it’s just way more expensive than you’d want. The schools here in California do it, and the steel superstructure is huge. Having done some steel moment frames for housing—let’s just say the cost isn’t in the panels. The moment arm for wind loads etc is not in your favor. My guess is you’re paying the cost of >10-20 panels to get 1 installed. Let’s call it a 15x cost multiplier. Even rooftop solar, which has a way worse multiplier (~4x) than power stations (2x?) can be hard to justify for some. You’re much better off covering the roof of the Walmart in panels than the parking lot. Which is why that is the case.

Yeah it’s a better use of land, it keeps the cars shaded, but no one seems to have figured how to do it economically. Even in Southern California where it’s very sunny, and power is very expensive. I just don’t think it’s anywhere close to being economical. And in other markets the economics are almost certainly worse.

[galaxyLogic]

> no one seems to have figured how to do it economically

Mass-production is the key to economies of scale. Government policies can play a huge role in steering us towards goals like that.

Why is America so rich? Because of car-industry. And why is car-industry so prominent? Because of the interstate highway system.

[MadcapJake]

There is a company working towards this that I believe has been mentioned here on HN before: https://www.legends.solar/get-early-access?grsf=texm9h (Feel free to lop off my referral code).

I'd argue that this is likely more challenging than it seems, with city/state/county building codes, plus just building on existing dense spaces, and add to that any grid/utility policies and associated costs to play ball

[Schroedingersat]

Probably a combination of insane zoning and tax laws that would make owning a parking lot that does something productive cost 10x as much as it yields and that landlords are as a rule stupid, petty, and greedy and demand a large enough share and dealing with them is so volatile that noone wants to take the risk.

[galaxyLogic]

Exactly. We need better laws

[galaxyLogic]

> why isn't this already a thing?

Perhaps the Inflation Reduction Act subsidies will, or should, make it a thing.

Government subsidies (incentives) is a good thing if it can save the planet and prevent the devastating floods and forest-fires and drought that is killing us now.

[spockz]

And car owners benefit in summer from cooler cars due to the shade.

[Fomite]

Makes the lots much more difficult to plow in the winter though. Not relevant for large swathes of the world, but a problem in a lot of places.

[galaxyLogic]

I don't think you need to plow if you have roof over you.

Snow covering the solar panels could be a problem. But perhaps even in winter there is a bit of sunlight which could produce electricity to warm up and melt the snow.

[ncmncm]

Actually not.

[bamboozled]

Everyone benefits from this

[cassepipe]

No. If the solution is to price in the externalities, it only makes sense for Walmart to pay for it. Their parking means less land with vegetation that can capture carbon and all the bad externalities that comes with land artificialization. Plus, they will probably benefit from it because else what are peope going to do when they come back in a car that unbearably hot (and extreme heat events, and extreme cold events for that matter, are going to more more frequent ) ? Leave the engine on for condtionned ? That would be crazy.

[ncmncm]

My local Walmart has solar over much of its parking lot. All the cars huddle under it.

Meanwhile, the store roof entirely lacks solar.

Nearby Safeway is opposite.

[galaxyLogic]

Good starts. Must start somewhere. We all want an electric car and a lack of charging stations is a problem. Therefore I would vote for starting with parking lots, they are closer to cars.

[Schroedingersat]

> No. If the solution is to price in the externalities...

I mean I'd love pricing in the externalities, but then it'd be moot because there'd be a building rather than a parking lot, no walmart, and a train or bicycle rather than a car. There'd also be plenty of roof area for solar panels in any place with a density lower than tokyo metropolis so you wouldn't even need to build supports.

[galaxyLogic]

It's not only companies providing parking lots for their customers. In big cities it is big business to provide parking for whoever needs it. Railroads need parking lots for their customers who drive to the station with their cars and park them there.

[galaxyLogic]

And the car-owner would win because their parking would be cheaper

[insane_dreamer]

Start with the Walmarts, Targets, etc.

[denkmoon]

Why downvoted? This exactly. Start with parking lots that hold say >100 cars. A business with that much need for customer parking can likely bare this cost, and if not they're probably close to losing their social license anyway. And they will absolutely take advantage of tax benefits and subsidies provided by every level of government to make it happen.

[MichaelCollins]

> This exactly. Start with parking lots that hold say >100 cars. A business with that much need for customer parking can likely bare this cost,

Say goodbye to all rural farmers markets.

[denkmoon]

Did you know gaming FACT: It is possible to add exemptions to legislation for edge cases and scenarios where the legislation would cause undesirable outcomes.

[boppo1]

Those lots gonna be gross and collect garbage and criminals.

[denkmoon]

As opposed to the existing concrete parking towers that usually smell strongly of urine and have accumulated so much garbage that it now acts as a patina on the asphalt...

[msmenardi]

Maybe we should make a bigger effort to keep them clean. But that's a separate issue that seems completely separate from whether or not they're covered in solar panels.

[smadge]

On the contrary it would likely kill large brick and mortar businesses like Walmart who depend on large surface parking lots and massive public investments in car infrastructures.

[MH15]

They've got smaller parking lots.

[dvirsky]

> Use all the excess solar/wind to create fuel for the natural gas plants

I don't know what the efficiency of the process described in TFA, but from Wikipedia I see that Electricity->Gas->Electricity has an efficiency of 30-40%. There are other alternatives like pumped hydro stations that are way more efficient.

[Schroedingersat]

There are not enough sites for pumped hydro.

Chemical energy is dense, easy to store, and you need methane for stuff like fertilizer.

Solar energy is basically free ($30/MWh and falling rapidly). The solutions we'lp use are the ones which scale and the ones which are cheapest for storage as it will be much more expensive than the energy.

For storing for a day, that's probably sodium batteries as the cost per MWh through is lowest.

For storing for a year, you want to minimize cost per MWh stored. Right now this looks like methane, maybe hydrogen or for heating, thermochemical batteries.

[ncmncm]

> There are not enough sites...

This is always claimed, and is always false. Please do not repeat falsehoods.

Existing hydro generation needs a watershed. Pumped hydro does not. All it needs is a disused hilltop and earthen dike, and not always the dike.

It doesn't always need the hill: underground cavities work to pump water up out of, and to drain into.

Batteries will always be the most expensive alternative. They will be used in limited amounts, mainly for very short-term (overnight) storage.

[Schroedingersat]

> It doesn't always need the hill: underground cavities work to pump water up out of, and to drain into.

Do you have any good numbers on real world projects? I'm very happy to be wrong here, but all the numbers I can find are either lies from nuclear shills or using existing watersheds. Most also only focus on the cost per kW which is higher than batteries and not the relevant metric (as batteries can drain in a few minutes) for season-long storage.

Also a quick back of the envelope seems to suggest emptying and filling lake Baikal could store as much energy as about a billion tonnes of chemical storage. This seems like a reasonable upper bound which would indicate pumped hydro is about an order of magnitude short of solving the problem. Current battery production is nowhere near (total cumulative seems to be about a megatonne chemical equivalent even if it is more than doubling annually it'll take over a decade to catch up), but this is expected because batteries are optimal for short term.

Overall by gut feel it seems a more feasible to make and store ten cubic kilometers of chemical fuel worldwide than move 200,000km^3 of water around.

[ncmncm]

Most current pumped hydro uses existing dams because duh. But nobody is building those anymore, for reasons you note. Existing hydro power dams were expensive because they needed to be deep to store years of water, and concrete because deep water has high pressure. They destroy ecosystems because that is where the water comes from.

Dedicated pumped hydro storage is typically quite shallow, with an earthen dike (if needed at all), and the only place with high pressure is at the bottom end of a penstock. It does not need to store years of water; just a day's worth is useful.

[Schroedingersat]

To follow up, fengning is on an existing river, uses an existing lower reservoir, has favorable geography, cost between $1.8 and $3 billion somewhere and stores 40GWh with 3.6 GW power.

This makes it better than existing batteries for ~1 day time scales and roughly on par with the upcoming generation of things like sodium batteries.

It's not a clear indicator as it's obviously optimized for power, but these all seem to be big advantages specific to the site which would indicate that an artificial reservoir would have trouble competing even against batteries.

Different sources have figures that differ by a bit (presumably projections vs actual) and most seem to have some mistakes. Here's one. https://www.nsenergybusiness.com/projects/fengning-pumped-st...

I could believe that you might improve storage/cost by a factor of 10 if you found a suitable reservoir by reducing power, but that seems to back up my initial assertion that you need specific geography and to significantly change the ecosystem fairly well.

As such it seems like it is not much better than a battery for displacing fracked methane, oil, or nuclear for mediating seasonal variability (which is what synthetic denser-than-hydrogen fuel is for as it is optimized for approximately zero cost per capacity at the expense of the highest cost per joule with competitive cost per watt).

Plus batteries still have a 10-20% efficiency benefit.

[Schroedingersat]

A day's worth puts it in the power limited regime where $100/kWh 4C batteries are already close to viable, and can use the 50x higher power per $ and higher efficiency for minute by minute arbitrage to offset costs. Do you have sources for real projects that can beat $60/kWh capacity and $600/kW power (what you'd be competing with by the time construction finished)? Moreover it also needs to beat hydrogen or methane storage (electricity->chemical-electricity) which (sans capex for tanks because I can't find good numbers, but I think it adds about 20%) is about $100/MWh out and $1000/kW using current technology including energy and projected to fall to somewhere around $40 and $500 in realistic timescales.

To make it impossible to mine more fossil fuels even for a mixture of slave-driving sociopaths unrestrained by law and theocrats actively seeking apocalypse we need to be able to use a MWh at night in mid winter that was produced at 2pm in summer for less than around $40 and then do it another billion times without hitting some resource limit. Hydrogen with storage is shockingly close, and if synthetic ammonia/methane or metal hydride get over the line, noone will look at fossil fuels again.

You seem to be telling me that pumped hydro is already there, but I can't find a decent source agreeing with you (or any numbers dealing with this use case for that matter).

[weq]

And destroy the earth. Hydro is not green energy, its an energy tradeoff. nuclear is much greeener then hydro. with nuclear, its only a possibility of screwing the environment. with damns, its garenteed.

[ncmncm]

Nobody is building hydro dams anymore, because there is noplace left to build them. Many are being razed, instead, to try to restore fisheries.

But pumped hydro is a completely different proposition.

Meanwhile, each dollar diverted to nukes from building out solar+wind+storage brings climate catastrophe nearer. The immediate cause for catastrophe will be global thermonuclear war triggered by ... more subtle ... effects of the change.

[peterashford]

How are you seeing hydro "destroying the earth?". New Zealand has a lot of hydro and we don't appear to be destroyed, as of yet

[Schroedingersat]

Hydro makes major changes to the local ecosystem and kills a lot of wildlife that can't breathe water. Although p\enty of things can live in a dam they're not what was there before. It also makes major changes downstram

People like to equivocate this with making entire countries uninhabitable or ongoing destruction.

It also requires vast quantities of concrete (and thus has high one time emissions)

We should still avoid it where we can now that we know better.

[philwelch]

> Hydro makes major changes to the local ecosystem and kills a lot of wildlife that can't breathe water.

It’s not that great for river fish, either.

[ncmncm]

This is not true at all.

Hydro power dams use up a watershed, but those are not being built for storage systems. Pumped hydro storage does not consume a watershed or harm wildlife or fisheries. Pumped hydro does not need concrete for construction.

Please do not repeat this falsehood.

[Schroedingersat]

Please show me a funded or built project (or even a plausible proposal or projection from past and current projects) in the global north that has a lower cost per capacity than Fengning Pumped Storage Station that has the following properties:

- Is at a site of a type that is available with over 100x the capacity of fenging (ie. a hill with a dirt berm would count if there are 4000GWh of hills that could be plausibly used somewhere). If it does this it will help, but is still several orders of magnitude shy of replacing fossil fuels.

- Fulfils your criteria about not destroying an ecosystem.

- Is not built on top of a past project unless there are enough of whatever the past project is to fulfll criterion 1 (ie. a quarry or mine is fine if there are many similar mines or a handful of immense ones) or the cost of repeating the project elsewhere is included.

- Can empty its reserves in 2 months

- Doesn't take up a prohibitive amount of surface area (is at least 20kWh/m^2 or at most 10x the size of a solar array to fill it).

- Has an operating cost under $30/MWh of stored and produced energy

Otherwise pumped hydro does not meaningfully exist as it cannot beat batteries (the thing that is a long way from being good enough to replace fuels) or must destroy a watershed or other ecosystem.

[dvirsky]

Nuclear can't store solar energy, I'm only talking about giant scale energy store, not generation itself. I'm all for nuclear FWIW.

[nagisa]

My intuition would be that it is overall cheaper in the long run to produce green hydrogen and build new or adapt existing plants so that they can consume hydrogen. Just a few percentage points in efficiency of the fuel generation would entirely negate any capital cost savings of reusing the old plants.

[natmaka]

New gas turbines are able to generating electricity by burning hydrogen (up to 100%).

https://www.get-h2.de/en/project-lingen/

[philwelch]

But there’s also utility gas. I wonder if hydrogen powered home appliances would be any good.

[adrianN]

> Everyone assumes that energy storage will be batteries

Power-to-gas has been the proposed solution for seasonal storage for a long time now. Few people who are interested in the topic believe that current battery technology can scale to store a couple of weeks worth of power. Maybe something like iron-air batteries, but the proven technology is elecrolysis optionally followed by upgrading the hydrogen to methane or ammonia.

[vegetablepotpie]

This would be great for utilities, who could keep stranded carbon burning assets for their operational lifetime.

Although the carbon emissions would be net neutral, Such a system would not be greenhouse gas neutral. Some methane from the natural gas plants will leak out. This is a gas that is 25 times more potent than CO2 over a 100 year timeframe [1].

Nitrous oxide, which is a byproduct of the combustion process, will be emitted and this gas is 298 times as potent as CO2 over a 100 year timeframe.

[1] https://www.epa.gov/ghgemissions/overview-greenhouse-gases

[ncmncm]

Ammonia is injected into gas turbines to scavenge nitrogen to prevent NOx production.

This is a solved problem. Please do not engage in idle, misinformed concern-trolling.

[vegetablepotpie]

I assume you’re talking about Selective Catalytic Reduction. Although you can reduce the amount of NOx from emissions using SCR, you cannot eliminate it. I would not call it a solved problem so much as a mitigated problem. Furthermore, with catalytic reactions involving ammonia, depending on ratios of ammonia vs the emitted NOx gas, and the age and quality of the catalyst used, you may see slippage, which is the injection of too much ammonia, which results in its release into the atmosphere. This too can result in the creation of NO2. Constant monitoring of the emitted gasses and maintenance is required.

Point here being that you could avoid this whole class of problem with energy storage technology. Although Lithium Ion batteries present their own technical issues to solve, there are other energy storage technologies that show promise [1].

Regarding your comment, you took a leap in assuming this was assuming it was idle, misinformed concern-trolling. It could be that I am ignorant of the NOx scavenging, it could be that I am aware of it and take issue with it. Both possibilities you ignored.

Please review the HN guidelines, you may find this passage relevant,

Please respond to the strongest plausible interpretation of what someone says, not a weaker one that's easier to criticize. Assume good faith.

[1] https://aresnorthamerica.com/nevada-project/

[ncmncm]

Apologies.

[ncmncm]

Deserts are about the worst imaginable place for solar panels. The only reason desert solar farms are constructed is that idiot investors think they are a good idea, and pour money into them.

Deserts are a dumb place for panels because the panels get hot and dusty. Heat cuts both conversion efficiency and panel lifetime. Accumulating dust can block as much as 80% of light.

The best place to site panels is floating on reservoirs and canals, where temperature is kept in check. Nobody knows how long floating panels could last. At the same time, they cut evaporative loss and biofouling, and provide complex habitat under for water creatures.

Next best is in farm fields, in rows with room for a tractor and equipment between. There, they cut heat stress and water loss, and run cooler than in desert or on rooftops. Most plants can use only a very limited amount of full sun in a day, and just endure more, welcoming shade. The panels produce year-round, complementing seasonal farm revenue.

A good way to deploy in fields is bifacial panels in vertical fence-rows running north-south to pick up morning and afternoon sun, during peak demand. Panels stay cooler, don't gather dust, and are out of the way of farm equipment; and fence mounts cost less than others. This works well in pasture, too, where livestock keep down weeds and benefit from shelter. (E.g., sheep produce better wool.)

For some crops, growing directly under (near-) horizontal panels protects them from harsh weather, often multiplying yield. A T-shaped mounting is practical here, with room under, and a gap between, for farm equipment.

Since the land is doing something else of value, there is no need to pack panels as tightly as they will go. There is way, way more viable dual-use farmland than could ever be needed for energy, so only the best places for it need be used.

Hydrocarbons are a poor choice of storage medium, because you need a source of carbon to make them, which is then released into the atmosphere when you burn it.

Hydrogen just needs water for feedstock. It is easily stored underground, including in used up fracking fields. It may be transported in liquified form, similar to LNG.

Ammonia needs just water and air as feedstock. It stores in liquid form under light pressure at room temperature, and transports well.

Hydrogen and ammonia are both massively valuable as feedstock for myriad industrial, transport, and agricultural processes, so when your tankage is full, all your excess production may be sold for ready cash.

[Aperocky]

> simply a form of energy storage

A very bad one at converting from/to electricity. Obviously, if you start from something else, e.g. dinosaur, then it's great.

But if you want to use it to store electricity, it's extremely poor due to the conversion involved, any kind of battery (and iron battery is a promising one!) is much better.

[ncmncm]

Batteries will always be the most expensive alternative.

[Aperocky]

For single use, sure.

[ephbit]

> ... any kind of battery (and iron battery is a promising one!) is much better.

Good luck trying to break even with as many batteries as would be needed for weeks or months worth of energy/electricity.

[ncmncm]

Nobody needs "weeks or months" of storage.

If local storage looks likely to be used up, and you can't schedule power from a transmission line, you order a shipment of ammonia from any of many tropical solar farms.

[ephbit]

Sure everyone does.

Let's say renewable electricity generation capacity increases significantly (which needs to happen as we all know), then due to fluctuations around the year of solar irradiation alone there need to be weeks if not months worth of electricity storage (in whatever form).

Ammonia is exactly that, storage of energy that gets converted to electricity, to keep up with grid demand. Ammonia then _is_ your weeks/months worth of storage.

[ncmncm]

Hint: many places do not, in fact, experience annual reduced insolation, and can produce equally year-round. We call those places "tropics", maybe you have heard of them.

Do you think utilities store months of fuel, nowadays? Or do they rely on regular deliveries? Do you think relying on regular deliveries of ammonia, in winter, would be much different from relying on deliveries of NG year-round, as today?

[ephbit]

> ... many places ...

Yet I'd assume _most_ places in the global west still have fluctuating irradiation and wind to a degree that makes weeks worth of storage necessary.

> Do you think utilities store months of fuel, nowadays?

The utilities probably only to a certain degree. But it doesn't really matter who stores the fuel, right?

> The United States has the world's largest reported strategic petroleum reserve, with a total capacity of 727 million barrels. If completely filled, the U.S. SPR could theoretically replace about 60 days of oil imports. [1]

These reserves are of course not used to supply power plants.

But I'd bet as soon as the renewable slice of electricity generation exceeds some 50-60 % of total supply, the authorities will not have days but weeks or maybe months worth of natural gas or hydrogen or ammonia stored to supply the grid (with according power plants) over extended periods of low renewable generation.

Just thinking about how essential the electric grid is for society to work, convinces me that it won't be days worth but significantly more.

[1] https://en.m.wikipedia.org/wiki/Global_strategic_petroleum_r...

As to deliveries from around the world. Any country will of course make a trade off between the political goal of independence or self sufficiency and economic considerations. Countries that have sufficient renewable electricity generation potential to be independent from external supplies will rather try to avoid external dependency, don't you think?

Which would require storage.

Also, imagine what happens as combustion engine cars get replaced more and more by EVs. The strategic petroleum reserves probably become less important and grid stability becomes more important. And I don't think the EV batteries are going to provide enough buffer to enable a stable grid all year round.

[aivisol]

> imagine most of the desert in California converted to solar What is an average life time of a solar panel? What happens after it ended its service? Can you recycle them or they will just end up in a massive landfill?

[adrianN]

https://www.epa.gov/hw/solar-panel-recycling

But I wouldn't worry about putting them in a landfill either. They're not particularly dangerous.

[ncmncm]

They will be recycled, because ultra-pure silicon is very valuable. Likewise, cadmium and tellurium.

Voicing worries about used up solar panels is cheap concern trolling.

[ZeroGravitas]

Carbon fuels are bad, fossil or not.

Same as Green Hydrogen, you'd only burn these if you couldn't directly electrify or battery power it.

Otherwise you're using electricity you could have used directly, to make the fuel at a big loss of efficiency.

[s_tec]

The main reason to keep hydrocarbon fuels in a green-energy future is for their energy density. Rockets and airplanes will always want the best density and weight available, and that’s hydrocarbon fuel for now, barring some order-of-magnitude battery improvements. Hydrogen rockets are a thing, but their tanks are huge compared to methane or kerosene rockets.

[thrown_22]

> Just keep building more and more solar/wind, as much as the land can handle (imagine most of the desert in California converted to solar).

This is called a dystopia.

[sneak]

IMO a dyson sphere is not a dystopia. Where is the line?

Is a desert covered in solar more or less a dystopia than the smog clouds that currently engulf LA?

[tppiotrowski]

I thought the smog is just dust from the desert. Isn't this why LA skies are so clear after a rainy day?

[sneak]

Smog is sulphur dioxide and other anthropogenic air pollution, mostly from vehicle exhaust and other sources of combustion.

[tppiotrowski]

I wasn't challenging what smog is. I was pointing out that LA air quality no longer suffers from smog like it did in the 1970s. Any hazy skies around LA are now more a product of dust in the air and not vehicle emissions.

[thrown_22]

That smog cloud is from China.

[ReadTheLicense]

Yes! The same way, using CNG or bio-diesel (for example wood or algae-derived) in plug-in hybrid vehicles with smaller batteries (50 km) would be much more ecological than large battery vehicles.

[marcinzm]

Would they be more efficient? Burning gas is horribly inefficient and has engines have weight as well.

[ReadTheLicense]

The conversion might not be as efficient but all cars having a 350km battery for the rare occasion when they leave the city 2-3 times a month seems like a bigger waste. They would normally use the 50km battery and the lesser efficiency would kick in only during long distance trips. Modern range extenders can be pretty lightweight... It could even be modular/take-out in your frunk.

[marcinzm]

>Modern range extenders can be pretty lightweight... It could even be modular/take-out in your frunk.

Not sure how that'd work. To get over 50km range you need a gas engine that provides 100% of the power to the car at highway speeds. A small engine won't pull that off.

[Schroedingersat]

Something built for efficiency (think aptera rather than tesla) can cruise indefinitely on a lawnmower motor or a mid range hardware store portable generator.

There are motorbike engines which produce 30kW (double or triple what a tesla needs to cruise) and can be lifted with one hand. Detune it for longevity, efficiency and noise, add a 10-15kW stator and a 10L tank and you can have a range extender which would take up less than half the boot of a sedan.

If we find our collective sanity and allow travelling long distance at 80km/h that halves.

Hell if we could get our act together and design sane sized vehicles with universal standards you could just stop and swap out a pair of 30kg batteries every hour or two.

[hexo]

Swapping batteries is a neat idea. Unfortunately it is a safety risk as you can't know its health.

>>> If we find our collective sanity and allow travelling long distance at 80km/h that halves.

I'd never want to travel 500km at 80km/h. That is nonsense. Also, having 30kW engine in a car on a highway is a life threatening risk, since you cant easily escape dangerous situations (overtaking other vehicles and acceleration at higher speeds takes way too long) - and we're not even talking about so absolutely hip and unnecessary SUVs or a fully loaded car.

[aurelianito]

That's not true. It needs to recharge a part of the electricity used. For example, if it provides 2/3 of the electricity being used it would potentially triple the range.

[bryanlarsen]

Which means it would have to run continuously. Which completely defeats the purpose of having a plug-in hybrid, which is to make most trips using only battery.

[weq]

They are more efficent because they last longer then current battery tech. China has miles of graveyards of green energy veichles. they are environmental hazzards after their useful life and run off rare earth minerals. not sustainable in any sense of the word; other then being an alternative source of fuel.