Yves here. Perhaps this is intel is stale, but it comes form a time when inflation-adjusted oil prices were similar to where they are now. I read then that the only environmentally-defensible biofuel was from Brazilian cane sugar. Part of the reasoning was the calorie cost of taking arable land out of food production; the other was the energy output of the various biofuels.
Can readers correct this information if needed? And are vegetable oils really OK for cars? I was under the impression that pure gas was better for longevity of cars than ethanol-adulterated gas.
By Felicity Bradstock, a freelance writer specialising in Energy and Finance. Originally published at OilPrice
- Biofuels have grown increasingly popular in recent years as a way to reduce emissions when it comes to both transport and heating.
- In the UK, around 1.7 million homes still rely on kerosene heaters, and the government believes those could be adapted to run on hydro-treated vegetable oil.
- In Mexico, there is a major push to expand the use of biofuels from cooking oil for public transportation, which would be a low-cost alternative for diesel.
Interest in biofuels has exploded in recent years, and as governments pursue both energy security and lower emissions, that interest is only rising. Following a flurry of new climate policies worldwide, energy companies are looking to reduce their emissions while ensuring the stability of their legacy businesses. Meanwhile, countries around the world are looking for energy sources that can be secured domestically. The U.K. and Mexico are two such countries, with both of them now looking to vegetable oil as a potential energy source for heating and transport. The use of cooking oils and animal fat in biofuel production is not a new concept, as several refiners in the U.S. use these products to produce fuels that entitle them to government tax credits. When gasoline demand plunged during the pandemic, oil companies were able to continue operations at their refineries by converting them to produce biofuels and taking the valuable government credits that came with them. The feedstocks came from used cooking oil and animal fat, which are typically deemed to be worthless – although they are sometimes hard to procure for that exact reason.
As several cities announce bans on the sale of new internal combustion engine (ICE) vehicles within the next decade, companies are racing to find alternatives to petrol and diesel, with the electric battery coming out on top. Some major automakers have also discussed the potential for the hydrogen fuel cell (HFCV). And others are looking to biodiesel to fuel the cars of the future. Biodiesel can be produced using animal fats and vegetable oil, significantly reducing greenhouse gas emissions on the roads. Vegetable oil can be used as a fuel for diesel engines as straight vegetable oil (SVO) or as biodiesel following conversion.
Biodiesel, which is generally viewed as cleaner and more effective in engines than SVO, is produced by a chemical process called transesterification, which involves a reaction with methanol using caustic soda as a catalyst. This reduces the viscosity and boiling point of the fuel, making it more like that of traditional diesel fuel. Most diesel vehicle automakers have approved the use of B5, a mix of 95 percent petroleum diesel and 5 percent biodiesel. And some manufacturers are making engines capable of running on B20 (20 percent biodiesel and 80 percent traditional diesel) or higher. However, the shift to using greater quantities of biodiesel has been slow to take off, with companies generally focusing on other green vehicle options, such as electric and HFCV.
But in recent months, the idea of using vegetable oil as a feedstock has gained more traction. In the UK, politicians are proposing the use of vegetable oil for heating in rural areas. A new bill encouraging the removal of duties on renewable liquid heating fuels, as well as incentives to reduce the use of kerosene in existing boilers, is being introduced to parliament by the former environment secretary George Eustice.
Around 1,7 million homes in the U.K. still rely on kerosene boilers, as they are not connected to the mains gas grid. There are already plans in place to ban the buying of new boilers from 2026, as homes switch to air-source or ground-source heat pump systems, but this new bill could help boost the uptake of green alternatives to kerosene between now and then. Eustice suggests that fitting new heating systems can be extremely costly, creating a “huge barrier” to uptake. This new bill would support homes across the country in the minor adaption of kerosene boilers to make them suitable to run on hydro-treated vegetable oil (HVO), which could reduce related greenhouse gas emissions by as much as 88 percent, according to Eustice.
Meanwhile, in Mexico, there has been a major push to expand the use of biofuels from cooking oil for public transportation. Mexico’s public transport sector continues to rely heavily on fossil fuels, with few incentives from the government to switch to less-polluting alternatives. But Jorge Tenorio, the CEO of Renov Biodiesel, suggests that biodiesel could be the alternative needed to power the transport system of the future. He explains, “The main raw material currently used in Mexico to produce biodiesel is used cooking oil. For every litre of recycled oil collected, one litre of biodiesel is produced, which is cheaper than the traditional diesel produced by PEMEX.” And the Advanced Biodiesel Cluster (BDA) of the Mexican Centre for Energy Innovation believes that 360 million liters of used oil could be obtained in cities of over 100,000 inhabitants, with the potential of providing a low-cost, clean alternative to diesel.
As interest in biofuels continues to grow around the globe, some countries are finally putting theory into practice by introducing major vegetable oil-produced biofuels into the energy mix. If new policies are passed on the use of biofuels, we could soon be fuelling the green transition on waste oils, previously destined for the drain or landfill.
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I drive a becoming-ancient ’96 VW Turbodiesel Passat Wagon. I did a fair bit of research on flipping to biodiesel from dino-diesel. It seemed that wear and tear on motor was a non factor. However, all fuel lines and fuels system gaskets etc are vulnerable to corrosion and need to be replaced. The kits and labor were in the $450 range. I eventually decided against, will make the shift if and when it occurs.
I am not seeing B5 or B20 in ‘rural’ Montana. The low-sulphur diesel blends are dry and require lubricant additives to properly lubricate the motor. One former Ford diesel mechanic told me he uses used transmission oil oil as a fuel additive. Only in the warmer months. It smokes some.
I need to read a lot more before I have the temerity for that one!
NB: MIGHT be the source of the Black Smoke that the redneck hell raiser diesel heads practice when passing bicyclists or grandpa putterers like me… Think particulate, dirty snow, diminished albedo, and warming. I probably should crush my car…
This article focuses on diesel, and home heating oil, waxier blends of fuel, not gasoline.
As to ethanol in conventional unleaded non diesel gasoline, I heard from our local chain saw repair and sales shop that all gasoline blends are really killing small motors, and fuel lines. I essentially handed him a perfectly decent small Husquavarna 2 cycle gas and oil fuel blend saw, irreparable, for his wall hanging collection. Fuels corrode the plastics and rubbers of the fuels system, the fuel goes ‘bad’ in a month or less, and requires stabilizers, even then the current blends go bad.
Right to repair only works if they still make the parts, the saw was made in the 70’s. Great little saw. sigh.
He recommended shifting to electric, or, had he been able to source parts, to doing the precise arithmetic, buying non-ethanol gas, in small saw fuel tank-sized quantities, stabilizing it, and using it all so it could not go bad and screw with the motor and fuel system workings.
My source was a septegenarian fairly conservative long-time small engine repair and sales guy with equanimity and no ax to grind or policy to deride.
90% of what he sells now are battery powered single battery for multiple implement systems (saw, hedge trimmer , leaf blower, weed eater suite systems). And, he’s competing with two big boxes, home despot and lows, so he is, like many things, and people, becoming an anachronism. I guess we will muddle through the shift away from oil to electric, many will not have the means to participate and buy the new technology. BTW, there are implications for lawn mowers here… time to xeriscape or wild to the meadow.
We eat oil, this shift will be very painful for very many on the lower rungs of our rotten wooden ladder to Mars.
Re chainsaws: Exactly, nothing from the petrol station goes anywhere near mine. Gums up the carburettor in no time. Local dealer (in Germany) sells high-purity petrol (or gas as you lot call it…) in 5-litre canisters. Same applies to four-stroke for generators. If I had ten grand to blow I’d get a pre-1990 Landrover, to run on veg oil when the time comes…
American gasoline is the same – gums up the carb, fuel line. If one is lucky here in the States, you can find a gas station that sells “recreational” fuel, which is non-ethanol. Much better solution than regular gas, even with additives.
Another alternative for the yard toys is aviation gas. If you have an airport that will sell it to you. No ethanol and higher octane, which might make them run a little hotter. You can also leave the gas in the machine over winter/summer. I’ve used it in my mower, weed whacker, blower, and snow blower for over 4 years now. Love it – even though it is more expensive – but worth every penny.
The elevated price of the fuel far outweighs the cost to have someone fix the durn things when they won’t start ($100 bucks the last time the snowblower wouldn’t start) because of a clogged carb. Plus the additives are not cheap, and I’m not sure how much they help.
Downside to aviation gas is that, as far as I know, it only comes leaded.
Swift already has an ASTM-approved unleaded alternative in the U.S. that can serve about 110,000 piston aircraft capable of flying on lower octane fuel – UL94.
I use vegetable oil as bar lubricant. The environmentally safe bar oil at my local chainsaw store had it listed as a the sole ingredient, but it was triple the price of grocery store vegetable oil, which works fine.
This is great information, thanks.
As i understand it, the whole “rolling coal” thing is mostly a case of adjusting the fuel mix to be far richer than normal.
I purchased a cordless battery powered electric chainsaw several months ago and it really works great. I was pleasantly surprised since I tried some electric yard equipment back in the 80s-90s and it really wasn’t very good, unless you only had about three blades of grass to cut through. It’s a 12″ blade and it goes through 6-8″ diameter wood with no problem. Not sure if you’d want to be a lumberjack doing heavy work with an electric chainsaw, but it’s fine for brush cutting and moderate sized logs.
The only drawback with this saw is it leaks bar oil. My father who is more handy than me noted that it was missing the o-ring on the oil cap and when I checked online, sure enough, these saws have been sold repeatedly with missing o-rings. Gotta have a little crapification thrown into pretty much everything these days – wouldn’t want to show up the competition with actual quality I guess.
I use supermarket canola oil as bar oil in my electric chainsaw. It’s cheap, and less disgusting when it sprays all over me and the wood being cut.
However, do your own research. I am an amateur.
It isn’t clear to me how you ruined your Husky saw. Instead of using cornless gas you ran some kind of cooking oil through it, or did you only substitute corn for regular 2 cycle lubricating oil?
Luckily I only have to drive 5 miles to find 89 octane corn free gas for my saw. A few years ago in Norway I noticed that the only gas sold at service stations was 95 octane. Now it looks like they are going with EVs.
Parts are unsupported for carb rebuild, gaskets, etc.
I looked on line, went to three small engine guys. Think Old Maytag washer that goes forever, versus 2020’s 3-year- program whirlpool. Its a feature, not a bug. Planned obsolescence. S L I C C .
Fuel line had collapsed and melded into a flat piece of plastic that would not transport as a ‘line”.
I have a 2003 VW Golf TDI that I can’t bring myself to get rid of
’03… a Holy Grail year. Its a sunk cost.
Rather than get rid of it, Drive only when necessary, and drive it til it quits.
Find a good touring bicycle, rig it with fenders racks and bags for commutting and shopping. Repurpose a bugger for hauling groceries, etc.
It can be done.
Your 03 has been built, the demands on the earth have been made. There is no free energy lunch. If it wasn’t grown, it was mined.
My resolution. Last car I will own.
I was shocked to see how few parts there are for my coddled ’96.. they brought 2000 in in ’96/97 to the entire North American market. My cracked windshield appears to be part of the package til the demise.
I started looking for a replacement, and was also shocked to see my diesel emits less carbon than a mid 2000’s corolla (another grail car). That one really surprised me. No word on particulates or NO2 SO2.
Doing less with less. That’s the ticket!
When the EU incentivized use of biodiesel/diesel blends, vast swaths of the rain forests of Sumatra were burned down to plant oil palm plantations. The smoke in far away Jakarta was so thick that people could scarcely breathe, and visibility was just a few meters. It was apocalyptic. As if that weren’t enough, the cost of cooking oil went up, making the poor even poorer. We should have learned from this terrible experience. Biodiesel should only be made from recycled waste oil.
EU love to toy with cobra effects.
The leaders of the EU don’t care about anything outside their “garden”.
The only difference between using diesel and veggie oil for a ***diesel*** engine is that the car’s exhaust (pleasantly?) smells like french fries.
As for the economics of it—-NO WAY….the developing world’s food supply has already been disrupted by western consumption of palm oil, cocoa, quinoa, etc.
The only theoretically good biofuels are fuels that use waste land and can be harvested 9-12 months of the year—-GW Bush’s bally-hooed, but dead end, switchgrass comes to mind.
Imposing food inflation on the developing world, just so that one’s Amazon fulfilment or road trip can be green-washed is unconscionable. In my opinion.
In the end all these “green” incentives seems to try to maintain a urban consumerist lifestyle that is plainly unsustainable, while still somehow save the environment.
It flies in the face of thermodynamics…
(seriously, physics, with thermodynamics in particular, is the true dismal science)
Farmers have used veg oil for machine fuel for over 50 years.
Louis Fyne above is correct. Biodiesel (via transesterification) and “renewable diesel” (via hydrotreating and also via gasification, pyrolysis, and other biochemical and thermochemical technologies, per https://afdc.energy.gov/fuels/emerging_hydrocarbon.html) are both acceptable fuels for diesel engines and work quite well in the application. Unlike ethanol in gasoline engines, there is no energy density hit nor moisture absorption to cause corrosion. And because it contains essentially zero sulfur, the emissions are slightly better.
So what’s the problem? There is NO WAY we can make enough. Per https://afdc.energy.gov/files/pdfs/3229.pdf, we could get 62.5 gallons of bio/renewable diesel per acre per year using soybeans. Even if we replaced all US cars with diesels that got twice the fuel mileage, we’d still need 67 billion gallons of bio/renewable diesel per year, which would require nearly 1.1 billion acres of farmland. [The US currently has 0.9 billion acres of farmland on 2.4 billion acres of land total.] If we added home heating oil and industrial uses, we’d need another 0.5 billion acres. If we wanted to fuel power stations this way, it’d be another 3.0 billion acres. We’ll run out of land before we’re finished.
I certainly see no harm in using waste oils in energy applications this way, but it’s a very limited commodity and will have a limited impact. [Kind of like burning wood scrap from the lumber industry in power stations.] But when you start tearing up vast tracts of land to grow crops explicitly for the purpose of burning them, it’s hard to see how we come out ahead environmentally.
Correct. Even if crops different from soybeans (there are several alternatives), and let’s say somehow more efficient, are used there is no way to make enough. Only marginal gains. It can be relevant for some rural communities but there is always the problem for land usage for this or that. We still need food, water, forests etc.
All true on the social/macro engineering aspects. There are things we should be doing, though.
1 – Nobody’s come up with a plausible electric airliner, so we’re going to need jet fuel from someplace. Luckily bio-diesel like processes could produce enough jet fuel, we need much less of it than ground transport fuel. Ditto when it comes to diesel for locomotives. We aren’t going to run overhead electric lines all the way across the great plains any time soon to convert diesel-electric locomotives into pure electric ones, but we could easily make enough bio-diesel for locomotives.
2 – With robust public transport, dependence on personal vehicles could be drastically reduced, allowing us to satisfy the our liquid ground transport fuel needs from renewable sources. I include here the new e-fuel technology which is energy intensive, but potentially carbon neutral.
Global climate change is an all-hands-on deck problem. We shouldn’t be worrying about silly, small economic concerns when it comes to addressing it. That means we should spend plenty of money developing biofuels, fuel cells, fuel cell infrastructure, e-fuels and all the rest. Any “wasted” R&D money still contributes to overall scientific knowledge.
Too many people think the personal transportation problem has been solved with battery electric vehicles when we’ve not yet solved the mineral supply problems or the battery recycling problem.
Its a long time since I’ve looked at comparative studies in biofuels, but generally they don’t come out well either environmentally or economically. The exception may be the use of waste oils from food or other processes (especially agriculture, which can produce vast mountains of waste material). There are some promising processes for converting many types of biowaste to liquid fuels.
They do have one key advantage though over other technologies – biofuels can use existing physical plant, whether vehicles or domestic heaters or commercial processes. Very little needs to be done to run a diesel engine on most oils, waste or otherwise. As such they can act as a genuine bridging fuel before a wholesale replacement of existing infrastructure and plant can be carried out. The potential benefits of being able to transition to a better transport/manufacturing/energy system over the normal investment lifetime (a quarter century or so) could make even sub-optimal biofuels a very useful tool.
The best thing for the soil which the bio-“waste” ultimately came from would be to compost the bio-“waste” back into compost soil-food to feed back to the soil it ultimated came from to begin with.
The next best thing for that same soil might be to semi-burn the bio-“waste” in CHAB units ( Combined Heat And Biochar units) to get some heat-energy out of the flammable volatile chemicals heat-driven off of the bio-“waste” while leaving the hard cell-structure carbon with its traces of non-volatile inorganic elements and compounds to add back to that same soil.
https://nfs.unl.edu/publications/combined-heat-and-biochar
http://fingerlakesbiochar.com/combined-heat-biochar-chab-markets/
Its not that straightforward.
Not all waste is suitable for composting in a large scale due to micro-contamination or bioacculative toxins. Human sewerage to take one very large example.
I’m an enthusiast for biochar, by far the best way to lock up carbon, but its not without its issues, particularly air pollution. Traditional charcoalers tended to have short lifespans for a very particular reason.
As with all these things, there is almost certainly no one ‘correct’ solution. We need them all.
That is certainly true for human sewerage. How much of that is due to industrial waste poured into the same sewer streams and how much is due to the many drugs excreted by human users is unknown to me. But both must be problems.
If we are speaking of agricultural waste specifically, such as bagasse left from crushing the juice out of sugar cane, surely returning it to the land the cane was grown on would be better than burning it as mere fuel. ( And if it were grown without toxic inputs, wouldn’t it produce a toxin-free compost?) Otherwise the organic material/humus levels in the canefield soil would be depleted over time ( or am I wrong)?
One would hope that burning off the volatiles from high carbon agri-waste would be done less pollutively than tradtional open-air charcoal making was. If it can’t be, then we have a problem. If it can be, then do we get the biochar without the pollution problems?
In my experience of testing, the overwhelming source of contamination for human waste is waste going via peoples bodies (contamination from industrial discharge to sewers is very locally dependent). And of course there is also micro plastics, mostly from domestic laundry.
Of course many agriculture wastes should be composted locally, but there are many examples where there is too much for local use and you either have to transport it a long way, or find some means of local processing (aerobic or anaerobic digestion, direct use as fuel, or some other processing). Examples would be waste from intensive chicken/hogs, commercial forestry off-cuttings, stubble from grain, or palm oil kernels.
In the Netherlands, about a decade ago, I knew a few people who ran their car on cooking oil (mixed with some diesel to make it thinner) because that was much cheaper (because it is taxed at much lower rates). The polite thing to do was to give the supermarket an advance warning so their workers didn’t have to stack 50 liters worth of cooking oil bottles on the shelves when you were going to take it off anyway.
I don’t know if it is common now. Prices of cooking oil have gone up and I have lost touch with these people. It is probably illegal too, because everything is, especially if it avoids some taxes.
Used cooking oil is often used, and if it works as well that seems more efficient.
Vegetable oils can be used in place of diesel with some modification.
They may require replacement of some gaskets and other sealers they react with differently from diesel.
They are also thicker, so require pre-heating for winter use to not foul injector systems. Also, I understand they make appreciably less power, but don’t know a value for that.
Biofuels used in this way are additions to diesel and is a big AG story in the past year. Seven or more new soybean crush plants in the US midwest alone are planned or under construction since mid 2022. Biodiesel production in the US was 971 m/gals in 2021, expanding to 1.9 m/gals in 2022. Canada is expanding its canola crush capacity by 62%, adding 6.8 m/tons of demand. Demand is described as insatiable and is instigated by gov’t mandates. Biodiesel used 28% of the US soybean crop in 2018. Impact in the US is considered to add $2 to $3 a bushel for soybeans. New crush plants in China and Brazil are underway.
About 12 years ago biodiesel fuel was readily available in northern Vermont and I used it exclusively in my 50 h.p. John Deere tractor without any modifications for two years. No problems at all and the exhaust smelled wonderful. And then something happened to cause the biodiesel fuel to go away. Someone said it became more profitable to send it to Europe. However, I know of two farmers who grew their own sunflowers and pressed their own biodiesel fuel. I think one is still producing it. I believe the diesel engine was developed in the early 1900s with the intention that it would be fueled by oil pressed from plants. Looks like there is a good future ahead for biodiesel.
On the energy theme, here is a video of the muddy battle between the police and the mystical climate warriors at the Lützerath open cast coal mine in Germany.
https://vm.tiktok.com/ZMYJaLujb/
The DOE has made ‘renewable’ the primary goal rather the ‘sustainable’. Look at the Netherland farming controversy. Farming is always renewable, no? What is more renewable than livestock?
https://www.marathonpetroleum.com/Newsroom/Company-News/Marathon-Petroleum-to-Proceed-with-Conversion-of-Martinez-Refinery-to-Renewable-Fuels-Facility/
Marathon is dumping a problematic California refinery and checking off ESG boxes at a nominal cost.
You take out the dubious biofuel contributions and our green energy transformation doesn’t look all that promising. And neither does burning garbage….aka municipal solid waste…sound that green. Politics is the art of the possible.
https://www.eia.gov/energyexplained/us-energy-facts/
biomass is 40% of renewables.
My old Mercedes 300D would run just fine on filtered waste vegetable oil. You have to pre-heat it to reduce the viscosity a bit. There were kits that ran the engine on diesel from the tank until the engine coolant was warmed up, then switched over. The engine on that car was pretty low-tech and not fussy about fuel (I used to get rid of spent transmission fluid by burning it off a quart at a time). I have a 2015 TDI Passat now – there is no way I could run it on vegetable oil.
As a tangential issue additional soybeans grown for food could provide more bean oil. There are three soybean markets, the bean itself, soymeal, and soyoil. The bean meal market could be a benefactor to an increase in soyoil demand. https://www.thenation.com/article/environment/climate-bean-new-deal/
“The United Nations went so far as to call pulses, a legume’s dry seed, the “food of the future” because of their low carbon footprint and high nutritional value.” Bean New Deal
for fun, here’s the https://mill.com/the-kitchen-bin for all food waste
German environmental minister is proposing to withdraw subsidies for bio fuels
https://advancedbiofuelsusa.info/german-minister-to-propose-withdrawal-from-use-of-crop-based-biofuels/
As others have said, anything that uses farmland for fuel to transition from million-year-old sunshine to currently received sunshine is going to be a problem. The acreage to grow the energy we currently withdraw from the fossil fuels in the ground is unavailable if we also want to eat. Which we do. Biofuels are fine as a transition technology but the only sustainable long term solution is a reduction in energy intensity on a per capita basis which means a dramatic reduction in driving or a dramatic reduction in the energy required for driving via much lighter vehicles (ebikes for example). A direct solar to fuel process using the sun on “waste” land would be a possible confounder. In all cases however, there exists a population at which the energy footprint per capita (driving or food or both) exceeds the sustainable level. Reduction in population however would be catastrophic for our current growth and debt based economic system. We must change voluntarily or we will change involuntarily. My money is on kicking and screaming.
My diesel knowledge is a bit stale now, but here’s what I remember from my diesel car buying research in ~2010, plus intel from some friends who worked at the Center for Diesel Research at the University of Minnesota.
– Vegetable oil can be used “straight” in diesel engines in some circumstances as long as the ancillary systems (fuel storage, fuel delivery and exhaust/aftertreatment) are designed with vegeteble oil in mind. A white spirit to reduce the viscosity of vegetable oil is necessary in many circumstances (cold weather). Some systems use a small tank of conventional diesel to get the engine warm before switching to vegetable oil.
– Biodiesel can be used as a direct replacement for diesel, again provided the ancillary systems are designed to accomodate it. IIRC, the problem with biodiesel is the difficulty of creating flex-fuel systems, particularly exhaust aftertreatment. Either the engine runs fine on petro-diesel or bio-diesel, but one which is agnostic to fuel blend is difficult to achieve. The now infamous Volkswagen 2.0 TDI warned profusely in the owner’s manual against using concentrations of biodiesel above 5%.
– I’ve forgotten the technical name for it, but there’s a process in which natural oils are converted to diesel basically by subjecting them to a refinery process. The resulting fuel is indistinguishable from petro-diesel from the engine’s perspective, but takes more input energy, and is therefore less environmentally advantageous. Also, IIRC, that process produced some fraction of gasoline and diesel from the same bio-oil inputs.
This info isn’t stale:
-Ethanol is actually a great fuel to substitute for gasoline from a performance perspective, especially in modern forced induction engines. The latent heat of vaporization and inherently good knock resistance lead to impressive power gains. These power gains can be converted to efficiency gains using tall gearing and low RPM boost management techniques. Flex fuel systems for pure gasoline up to 85% ethanol are a stable, reliable technology. There are trade-offs though. An engine optimized for E85 would have excellent efficiency, but likely wouldn’t run on E10.
As previously stated, ethanol fuels can pose problems for unsophisticated engines with carburetors and elastomer seals in the fuel system which are not ethanol compatible. Small engines for which this is a problem can be replaced with modern battery electric systems. I have an electric riding lawnmower.