# Why battery-powered aircraft will never have significant range

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#### rv6ejguy

##### Well-Known Member
New tech reactors and thorium ones may offer some advantages over the present technology but the big question is, will people allow them to be built? It seems nuclear has lost some of its shine in the last 10-20 years in many countries and only China seems to be building a lot of new ones.

Perhaps the drive to electric and climate concerns will change the perceptions.

#### Vigilant1

##### Well-Known Member
Lifetime Supporter
2) Yes, P-239 amongst other rare elements. And while some of these elements have potential military value, they are all contained in solution with many other elements - you can't just 'take it out' or steal it and use it for weapons.
True, but getting all the plutonium out of that solution is a very straightforward chemical process, much easier than separating/enriching one isotope from others of the same element. Every isotope of P can be used for weapons (though isotopes other than P-239 can result in very inefficient ones).

None of this is an argument against the existence of breeder reactors. But, as the possession of suitable fissile material serves as the only remaining brake on the construction of nuclear weapons by state- and non-state actors, the control of that material is exceedingly important.

#### Voidhawk9

##### Well-Known Member
HBA Supporter
...the big question is, will people allow them to be built? It seems nuclear has lost some of its shine in the last 10-20 years in many countries and only China seems to be building a lot of new ones.
Exactly so. There are plenty of interests keen to keep the public fearful of the nuclear boogieman. If not resolved, we hand the energy future (ie everything) to China.

True, but getting all the plutonium out of that solution is a very straightforward chemical process, much easier than separating/enriching one isotope from others of the same element. Every isotope of P can be used for weapons (though isotopes other than P-239 can result in very inefficient ones).

None of this is an argument against the existence of breeder reactors. But, as the possession of suitable fissile material serves as the only remaining brake on the construction of nuclear weapons by state- and non-state actors, the control of that material is exceedingly important.
Easy to solve - don't separate it out, and it is consumed in producing power with the other fissiles.
No state or non-state actor can break into a facility that doesn't extract Pu and steal it. They'd have to get in, take a quantity of the whole of the mixed fuel fluid, somehow escape with this very hot and radioactive liquid in a substantial quantity, take it to a processing facility of their own (without the bright radioactive signature of the stolen materials being tracked), process it, then build a weapon to utilize it (ie their own Manhattan project).
Anyone attempting such a thing would die of lead poisoning in step 1, I suspect.

#### Vigilant1

##### Well-Known Member
Lifetime Supporter
Deleted by author.

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#### Victor Bravo

##### Well-Known Member
HBA Supporter
A Thorium reactor the size of a 40 foot sea container, and buried underneath the local police or Sheriff station for security, could power a small town with electrical power. People could live 40-50 miles out in the country with inexpensive land, charge up their electric commuter airplane (Lavorini electric Flea... electric Luciole, Davis DA-5E) and commute to work in the city. Little or no nuclear waste, little or no realistic chance of somebody turning it into a weapon, no water pollution, no dead crops, no dead livestock, no glowing schoolchildren...

#### mm4440

##### Well-Known Member
The reactors that can "burn" existing waste seem like a no brainer. The fuel can have negative cost. Coal has killed many times the people than all the nuclear industry but it is scary and grossly overregulated. The new reactor designs are inherently safe, they depend on gravity and physics to shut themselves down rather than people, pumps and and other safety subsystems. Alvin was a smart cookie. Eric Raymond has demonstrated that solar electric sailplanes work. The big challenges are practicality, utility and affordability.

#### dog

##### Well-Known Member
As far as the concerns around nuclear weapons proliferation goes,isnt that enough of
a failure mode to just keep the raw fuel in the ground?Add to that all of the huge problems with fuel production,storage,transport,that must happen with absolute inventory control,
ya right,and its only a matter of time till something gets out of hand.
Limitations in the ability to distribute power mean that megga sized ultra secure facilities
just dont work,not counting strategic and enviromental concerns.
Solar is less interesting to watch work than drying paint.
We are all here because we love flying and the
mechanical aspects that make it possible.
Its impossible to overlook the basic risk of
mechanical complexity,and how each added
system in a mechanism(nuke plant or complex aircraft) has guaranties future problems and makes servicing more difficult.
Solar has no moving parts and has an excellent
record of reliability.

#### tspear

##### Well-Known Member
Not at all. We're both speaking anecdotally, so neither of us could claim absolute proof. But I'm always open to empirical evidence. So few people use it these days, but I got addicted to it in college statistical analysis classes. I confess that I hate to be proven wrong, but I do acknowledge when it happens. And yes, it does happen. Just please do me a favor. If you do prove me wrong, try not to make a habit of it. My fragile ego might not survive otherwise.
From 2015: New Study Reveals When, Where and How Much Motorists Drive | AAA Newsroom
and: The Average American Drives This Much Each Year -- How Do You Compare? | The Motley Fool
From 2021: Average Miles Driven per Year in the USA | Policy Advice

What I cannot find is the median daily mileage. I think that would be of more value.
Basically, the general public does not drive nearly as far we imagine.

Tim

#### BBerson

##### Light Plane Philosopher
HBA Supporter
A Thorium reactor the size of a 40 foot sea container, and buried underneath the local police or Sheriff station for security, could power a small town with electrical power.
Nuscale has a small buried modular reactor. A small reactor in the city can also send hot water to heat homes and electricity to charge electric cars at night and day. Doubles the efficiency using the normally waste heat.

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#### rv7charlie

##### Well-Known Member
I've been fascinated with nuclear power since I was in elementary school (late middle of the last century) and read everything I could get my hands on back then. I learned all about how reactors were self limiting, and couldn't melt down, by design. Fast forward a couple of decades, and we had 3 Mile Island. Another 5 yrs, and we get Chernobyl. Another 25 years, and we get Fukushima. Interspersed through all that time are all the incidents that through various miracles of luck, never got bad enough to make the news. Yes, outright disasters are rare, but when they happen, they tend toward apocalyptic proportions.

All this time, the nuke industry has been telling us that the reactors 'can't melt down' and are 'safe'. Now, the newer stuff may well be safe, and self limiting, but I've been told that before. Should I just accept the word of the same people who told me the same thing in the past?

I'm confident that safe nukes *can* be designed and built. I'm not confident that financially motivated corporations *will* design nukes that are safe, if they can save a dollar a month in operating costs by allowing them to be less safe. I'm also less than confident in the basic intellect of the designers. Fukushima was built on the coast, at basically sea level, in a country that's experienced earthquakes and tsunamis for thousands of years, and the designers put the diesel generators, which are absolutely required to keep the reactor from melting down (bizarre in itself), IN THE BASEMENT. I may not be the sharpest knife in the drawer, but...

Nukes could save us from all our power problems. But who'll save us from the corporations and the 'military-industrial complex'?

BJC

#### Vigilant1

##### Well-Known Member
Lifetime Supporter
Solar has no moving parts and has an excellent
record of reliability.
Yeah, reliably absent over 50% of the time.

Solar has a place in the mix. Wind, too. But until very cheap and reliable storage is actually fieldable, they will be bit players. Power produced when it isn't needed isn't very useful right now. And theoretical power production that isn't available when demanded is a cruel joke to folks who need to keep their house warm.
Intermittent power sources drive up the cost of electricity by requiring extra (truly reliable) power generation to remain in existence and ready to go, but not producing. Then, solar proponents point to those sources and say "look how expensive they are per kilowatt that you produced! Buy more cheap solar and wind!' Yeah, cheap.

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#### Hot Wings

##### Grumpy Cynic
HBA Supporter
Log Member
From 2021
Just about right for the wife's car. She has a short commute and the Subaru gets on the inefficient end of the bell curve for modern cars . We use it for road trips - about twice a year. (500G/year) Made me look up some numbers that I found interesting:

Per the EPA a gallon of gas has a KWH value of 33.4. At the cost of electricity here the break even point is about $3.70/gallon. If I assume that the 'buru gets 50% efficiency then the break even is$1.85/gallon*.

500gal/year x (current gas $2.90 -$1.85 KW equivalent) = savings of $525 per year. Of course that doesn't include the disparity in maintenance costs of the 2 fuel types with the electric being much better (short term). Our house is maxed out on the electrical panel after finishing the basement so to upgrade for home charging would take about 6 years worth of savings to break even.......just to be able to charge. It will be interesting to see how the, out of pocket,$/joule for the various energy sources works out over the next decade.

* includes $0.42/gal state and federal tax. If the same were added to electricity for 'road use' by energy x efficiency the cost of my pre-tax electricity would have to go down 23%. We have a$1/megawatt hour tax on wind generated electricity.

#### Vigilant1

##### Well-Known Member
Lifetime Supporter
If I assume that the 'buru gets 50% efficiency then the break even is $1.85/gallon*. I think 50% efficiency is way optimistic. From fuel to tire, I think it is closer to 25%, maybe less. ETA: I found this. Where the Energy Goes: Gasoline Vehicles EPA says gasoline cars have overall efficiencies of 12%-30%. Last edited: #### Vigilant1 ##### Well-Known Member Lifetime Supporter Our house is maxed out on the electrical panel after finishing the basement so to upgrade for home charging would take about 6 years worth of savings to break even.......just to be able to charge. Ouch. IF the electric car would be at home in the daytime a lot, and IF you have a good place to mount solar panels, this could be a good application for non-grid tie solar. When the car is full, dump the "free" power into an electric heat element in a domestic hot water preheated tank. As a bonus, if you lose grid power you'd have daytime emergency power to charge tools, run the freezer, a window AC unit, or your furnace blower, etc while the sun shines. Run essential small loads at night off the car battery. A regular 115VAC, 15 amp receptacle in the garage/driveway on an existing circuit could be the backup charger for the car if you need to get a bit of juice overnight for a short commute. Panels now cost about$1/watt (good used ones are 1/4 of that), and if they last 25-30 years, you might do pretty well, esp if the prices of electricity and other fuels go up (seems likely).

Just what you need, another fun project alongside the shop, the Fauvel(s), the V-twin, VW heads, etc.

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#### rv7charlie

##### Well-Known Member
It's unlikely that the panel is 'maxed out'. Most modern houses have 200A main breakers, and you'd have to really try to exceed 130A. Two 30A AC units, a 40A oven, and maybe 20-30A worth of lights, TVs, etc.

#### ElectricFlyer

##### Well-Known Member
HBA Supporter
I have no problem with Nuclear power -- as long as legislation brings in the mandate that every house in the 20 mile area gets retrofitted with a free heavy water swimming pool... just think, it wont freeze in the winter time, once you get your radioactive waste deposit that is.

#### tallank

##### Well-Known Member
If there was a real new battery on the horizon it would be the hottest stock on NASDAQ. There are many new technologies being looked at in Universities but none have made it to market.
There is a very basic law of physics that limit what a battery can do compared to fossil fuel. The internal combustion engine consumes 14 lbs of air for every 1 lb of fuel burnt. We do not have to carry that 14 lbs of air per gallon of fuel. A battery has to have all of its components included. So right off the battery has a 14 to 1 weight disadvantage over the internal combustion engine.

#### Victor Bravo

##### Well-Known Member
HBA Supporter
Slightly further OT, sorry, but my nuke power comments above included the idea that there has to be a working deterrent against corporate rodents sacrificing public safety. Personal, direct liability of each and every executive associated with the nuke plant, with no "corporate veil" LLC or C-corp protection. The Board of Directors lose their homes, their kids lose their tuition to Yale, and they even wind up in Club Fed if someone actually gets hurt. A law that intercepts and invalidates the corporation's liability insurance, and exposes the entire pool of shareholders to the liability. There's nothing like the threat of taking a rich person's money away to make them pay attention to something.

#### Hot Wings

##### Grumpy Cynic
HBA Supporter
Log Member
Just what you need, another fun project alongside the shop, the Fauvel(s), the V-twin, VW heads, etc.
That is only about 40% of the projects................The list is getting shorter but not fast enough to suit me.

The panel isn't maxed out on amps - just space and there aren't double breakers for that particular model. I could do a sub-panel for less $'s but there are other limitations/problems with the electrical that only a new service will fix. A wind generator* is going to be added the list when 2 of the above have been completed. Local ordinance limits us to 3 Kw units so it's kind of a 'as time permits' project. *Irrelevant bit of wind power trivia: We have about 900 old fiberglass wind generator blades buried at our land fill at a cost of about$600 per blade, for the hole.

#### Vigilant1

##### Well-Known Member
Lifetime Supporter
There is a very basic law of physics that limit what a battery can do compared to fossil fuel. The internal combustion engine consumes 14 lbs of air for every 1 lb of fuel burnt. We do not have to carry that 14 lbs of air per gallon of fuel. A battery has to have all of its components included. So right off the battery has a 14 to 1 weight disadvantage over the internal combustion engine.
??The battery is just storing electric energy via a reversible chemical reaction. The IC engine is performing an irreversible conversion of chemical energy to physical motion. They are so different in concept and function that just the use of O2 by the IC engine doesn't do much to explain all the differences.
It's the (practically) available energy in the chemical bonds of the battery vs the fuel that explains the difference in specific energy between fuel and a battery. The use of atmospheric O2 isn't the explanatory factor, per se.
A very inefficient combustion engine system could have an overall energy density worse than a battery and electric motor.

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