Can solar powered aircraft save GA?

[TangoEchoAlpha]

http://www.sunflyer.com/#!programs/mainPage

Their website claims the aircraft produces only 55 dB of noise*. Suffice to say, I'm a big fan. And it's got solar panels too! I wouldn't mind a few more aircraft with solar cells on the wings. The idea of an airplane that can generate it's own power is very exciting.

Could this revive GA by drastically lowering the operating costs? Will GA ever become a hobby accessible to the everyman?

*For reference, here are the noise levels inside a variety of cars. http://www.auto-decibel-db.com/ This shows that the 55dB noise level of the Sun Flyer is lower than nearly all production cars driving at highway speeds. In fact, it's QUIETER THAN A PRIUS!

 

[ircphoenix]

The idea is interesting. But right now it isn't even remotely feasible without energy storage mediums that perform at much better storage/weight capacities.

Think in terms of conventionally powered aircraft... a 150 HP O-320 engine has a dry weight of 244 lbs. Say you have 50 gallons of 100LL on board to feed that engine. That's another 300 pounds. Round it up to account for wiring harnesses, oil, fuel lines etc. and you have 600 lbs of energy generation for the ability to go 500 nm and stay in the air for 5-6 hours.

Now if you look at something like the Tesla Model S P85D with a range of 320 miles, that vehicle requires 1,200 pounds of batteries *alone* without accounting for motors, wiring, and other stuff. Throw in the weight of solar panels and charging equipment, and you're looking at a bird that is pretty damn heavy and expensive before you even start adding people and baggage.

I'm a huge proponent of electric technology, and I love me some Tesla... but I think power generation and power storage need to advance way beyond where they're at to offer any kind of cost savings over current GA technology.

 

[kayoh190]

Some of the direct operating costs will be lower, but much of the other stuff doesn't change. You still have to hangar it, insure it, annual it, pay for routine MX, and so on. What will the purchase price be? And this all assumes they get the technology to where they can build an airplane that competes reasonably well with what's already out there, and they're still a long ways away from that.

Don't get me wrong - I love the idea, but we're talking what, maybe $60-100/hr in savings between fuel and oil? That's not my barrier to entry. My problem with GA is that a new Cirrus costs north of a half-million dollars. A friggin' 4-place single engine piston. I personally love aviation enough that I'd have no problem spending $100K on a 40 year old airplane, or go play on the experimental side. It certainly doesn't bother me that I pay $150/hr to rent a plane with cracking plastics and an interior straight out of Boogie Nights. But GA needs everyday upper-middle class folks, and I don't think many of them see things the way I (or most of us on this board) do.

 

[cowman]

Some of the direct operating costs will be lower, but much of the other stuff doesn't change. You still have to hangar it, insure it, annual it, pay for routine MX, and so on. What will the purchase price be? And this all assumes they get the technology to where they can build an airplane that competes reasonably well with what's already out there, and they're still a long ways away from that.

Don't get me wrong - I love the idea, but we're talking what, maybe $60-100/hr in savings between fuel and oil? That's not my barrier to entry. My problem with GA is that a new Cirrus costs north of a half-million dollars. A friggin' 4-place single engine piston. I personally love aviation enough that I'd have no problem spending $100K on a 40 year old airplane, or go play on the experimental side. It certainly doesn't bother me that I pay $150/hr to rent a plane with cracking plastics and an interior straight out of Boogie Nights. But GA needs everyday upper-middle class folks, and I don't think many of them see things the way I (or most of us on this board) do.

I think this is absolutely right. Cost is a HUGE factor for most people

According to wikipedia, in 1956 a brand new Cessna 172 cost $8,700. In 2016 dollars that's about $76,000. No, that's not cheap but well within the range of possibility for a middle class person who wanted one. What the heck happened? It's not like the airframes or engines got that much more advanced, they're still selling pretty much the same 172. I realize the avionics have improved a lot but that doesn't even get us close to explaining the price discrepancy. Some say liability costs or production volume or more regulation... I have no idea if any of this common wisdom is true though does anyone actually know?

Look at what our repairs and upgrades run. $30k for a piston engine with 1950's technology, $15k GPS units? Are you kidding me? Those of us who pay these costs just want it that bad, you have to know on some level that you're paying 4-10x what these sorts of things ought to cost. And even if you can justify this somehow as "reasonable" most normal people can't afford things like this and the training and the recurrent training and fuel, and so on...

 

[Hank S]

Solar power will not save GA.

There is, however, an outside chance that solar power may be able to save itself. It's been teetering on the edge of extinction since the 70s, even with massive infusions of government funding.

 

[Somedudeintn]

Some of the direct operating costs will be lower, but much of the other stuff doesn't change. You still have to hangar it, insure it, annual it, pay for routine MX, and so on. (

Who is going to hangar a solar plane?

I can see something like this working as technology improves. I think battery energy density is the biggest technological hurdle right now. Even if that were not an issue I still think it would be a very niche market.

 

[frfly172]

For the weekend pilot the electric airplane has possibilities .could work out fine for the fly for the 100 dollar Hamburg runs.

 

[Dr. O]

When the gummint discovers you are flying on batteries there will instantly be regs that the batteries have to be certified, have an inspection every X number of recharges, be tested annually, the electric motors have to have an STC, be wound with approved wire, and maybe even the electrons involved will have to come from a certified source (we can't have uncertified electrons running around inside of an "airplane" motor, now can we.) If you think LiPo batteries are expensive now, wait till the FAA gets involved.

 

[Shepherd]

In the history of aviation has any new technology "saved" General Aviation? IMHO, no.
In the history of aviation has any technology improved General Aviation? IMHO, yes.
In the history of aviation has the government managed to screw up gains made by General Aviation? IMHO, every time.

 

[Shepherd]

Who is going to hangar a solar plane? .

Anyone who has a solar plane will absolutely put it in a hanger.
You can put a whole lot more solar panels on a roof of a hanger than on a wing of an airplane.

 

[GRG55]

A practical electric plane is coming. The training market, with "return to base" operations, is a good application given the energy density limitations of current battery technology. The realities of the GA environment in Europe appears to be driving development on this front faster there than in the USA at this time. Once these things are sufficiently developed to get beyond the training market the shorter distances between destinations in Europe (compared to the vast size of the USA and Canada) will probably facilitate a proliferation there.

Airbus is working on one they call the E-Fan, and Siemens has designed an electric drive motor for it specifically for the high output & light weight requirements of flight:
http://www.flyingmag.com/aircraft/meet-airbus-e-fan

Slovenia's Pipistrel has also been working on an electric plane:
http://www.flyingmag.com/aircraft/new-electric-trainer-pipistrel-takes-flight

Some limitations?
- Teaching the basics of flight will work in an electric airplane, but it won't completely prepare students to operate a conventional avtgas powered airplane, much less a turbine.
- Battery technology isn't likely to advance in leaps and bounds (despite what Elon and other cheerleaders would wish us to believe). It is chemistry and the advances in capacity and greater energy density per unit of battery volume or weight are probably going to be incremental, not breakthrough.
- There are some safety implications, as the "melting batteries" in the Boeing 787 and the occasional spectacular fire that reduces a Tesla to ashes demonstrates. An intense in-flight fire is a nightmare, and that is a real engineering issue with chemical batteries being pushed to their limits.

 

[N659HB]

Where do we stand with fuel cell technology?

 

[GRG55]

Where do we stand with fuel cell technology?

They need a continuous source of fuel - hydrogen or methane gas from which the hydrogen molecules are used. Well developed technology that seems to be having more success in stationary applications. Have not yet proven commercially viable in ground based mobile operations (trucks and buses).

 

[N659HB]

They need a continuous source of fuel - hydrogen or methane gas from which the hydrogen molecules are used. Well developed technology that seems to be having more success in stationary applications. Have not yet proven commercially viable in ground based mobile operations (trucks and buses).

Hmmm. Thought they used these for the Apollo missions.

 

[Sundancer]

Probably not worth the effort (electric airplanes) this decade or so - I mean, they probably will be semi-practical, but why? Unless fuel costs go through the roof? I could be wrong, but if so, I still don't think electric "saves" GA. The product, produced in low volumes would have to be much cheaper to buy and operate than a reciprocating engine equipped airplane. Maybe with an "Auto-fly" feature and a "save-me" chute, they might sell O.K.

 

[ircphoenix]

Probably not worth the effort (electric airplanes) this decade or so - I mean, they probably will be semi-practical, but why? Unless fuel costs go through the roof? I could be wrong, but if so, I still don't think electric "saves" GA. The product, produced in low volumes would have to be much cheaper to buy and operate than a reciprocating engine equipped airplane. Maybe with an "Auto-fly" feature and a "save-me" chute, they might sell O.K.

The only issue I have with this statement is there's an inherent assumption that fuel costs will remain fixed indefinitely. We learned during the last gas spike that fuel prices do not remain fixed... the American auto industry almost went completely belly up because they assumed cheap gas was a forever proposition.

The ideal time to research alternative energy is when conventional prices are low.... because increased reliance on things like solar/wind helps keep conventional fuel prices low, as it lowers demand for it. If you wait until fuel prices are astronomical, then you've already lost the battle since there's spool up time associated with alternative energy research/production.

 

[vontresc]

I have two solar powered aircraft, and they are great fun. Granted, I still need a pawnee to tow me up though

 

[TangoEchoAlpha]

TWO?! Well that ain't right considering how some of us don't even have one. Ah well. Someday...

 

[Hank S]

Solar powered planes will be terrible for the rental market! Very few back-to-back flights. It takes so much longer to recharge the batteries than to top off the gas tanks.

They will be miserable for owners, too, whose travel will be limited to very short distances. How long will it take to reach Oshkosh if you must land every 2-1/2 to 3 hours for a 3-4 hour recharge? Or are the solar cells in the wing supposed to provide just as much power as the motor uses? Fat chance of that, if the plane flies fast enough to travel in. And very limited IFR flight, too. (I've gone 2-1/2 hours in the clouds, landed under a solid overcast, then flown home later the same day. Solar? Not a chance . . .)

 

[GRG55]

Hmmm. Thought they used these for the Apollo missions.

Affirmative.

It's called an alkaline fuel cell and uses hydrogen and oxygen in combination to produce both electricity and potable water for human consumption. The hydrogen and oxygen fuel were carried in liquid form on the spacecraft and consumed during the mission.

The larger fuel cell was in the Apollo Service Module, and it was one of the liquid oxygen fuel source tanks that ruptured to cause the mission abort of Apollo 13.

In the "earth bound" fuel cells (such as Ballard's proton exchange membrane technology fuel cells) the oxygen is usually sourced by using air, but the cells still need a continuous source of hydrogen fuel.

 

[GRG55]

Probably not worth the effort (electric airplanes) this decade or so - I mean, they probably will be semi-practical, but why? Unless fuel costs go through the roof? I could be wrong, but if so, I still don't think electric "saves" GA. The product, produced in low volumes would have to be much cheaper to buy and operate than a reciprocating engine equipped airplane. Maybe with an "Auto-fly" feature and a "save-me" chute, they might sell O.K.

Fuel costs are only one variable. Listen to the tone in the OP. It's coming from a generation of people that are going to have as much influence reshaping our world as we Boomers did starting in the 1960s.

If we want to attract the next generation of potential pilots into GA in any quantity we aren't going to do it with clapped out 172s and Cherokees, or even with Rotax powered LSAs.

People don't buy $5000 bicycles or $100,000 Teslas because gasoline is expensive. Many (Most?) of them are attracted by the perception the bike or the Model S is a technology platform more advanced than the alternatives. I can see an electric airplane creating a similar reaction.

The homebuilt movement went from a bunch of guys gluing wood ribs and covering the result with fabric to hot wired foam and composites & CNC matched hole drilling in aluminum. Those advances attracted a lot of people into the movement. LSAs have helped the commercially produced light plane GA market stay alive, but it needs to do something more to have a vibrant future.

 

[Everskyward]

Solar powered planes will be terrible for the rental market! Very few back-to-back flights. It takes so much longer to recharge the batteries than to top off the gas tanks.

They will be miserable for owners, too, whose travel will be limited to very short distances. How long will it take to reach Oshkosh if you must land every 2-1/2 to 3 hours for a 3-4 hour recharge? Or are the solar cells in the wing supposed to provide just as much power as the motor uses? Fat chance of that, if the plane flies fast enough to travel in. And very limited IFR flight, too. (I've gone 2-1/2 hours in the clouds, landed under a solid overcast, then flown home later the same day. Solar? Not a chance . . .)

I have seen a presentation by the Sunflyer folks and they are realistic enough to know that the current iteration is not a cross-country airplane for private owners. It's meant to be a trainer. They have hopes for the future but realize the limitations of the current technology.

 

[GRG55]

I have seen a presentation by the Sunflyer folks and they are realistic enough to know that the current iteration is not a cross-country airplane for private owners. It's meant to be a trainer. They have hopes for the future but realize the limitations of the current technology.

In the ground vehicle world the largest adoption of alternate fuel technologies is in the "return to base" applications. Waste hauling trucks, civic buses, package delivery vans and other vehicles that do a route and return to their fueling station at the same starting point are now commonly using compressed natural gas (CNG), hydrogen fuel cells, propane, and so forth. For private cars its probably going to be the "commute to work" with the weekend trip to the golf club, recharging at home at night, that may be among the early adopters of electrics. The training market is the aviation "return to base" equivalent and makes perfect sense to target early on.

Might be well to remember the first step to the moon was Alan Shepard's suborbital "return to base (earth)" flight in Freedom 7.

Just like most automobile trips are close to home, most light airplane trips probably end up with the airplane back at its home airport at the end of the day.

 

[Everskyward]

In the ground vehicle world the largest adoption of alternate fuel technologies is in the "return to base" applications. Waste hauling trucks, civic buses, package delivery vans and other vehicles that do a route and return to their fueling station at the same starting point are now commonly using compressed natural gas (CNG), experimental hydrogen fuel cells, propane, and so forth. For private cars its probably going to be the "commute to work" with the weekend trip to the golf club, recharging at home at night, that may be among the early adopters of electrics. The training market is the aviation "return to base" equivalent and makes perfect sense to target early on.

Just like most automobile trips are close to home, most light airplane trips probably end up with the airplane back at its home airport at the end of the day.

In the car market solutions are appearing. Within the past month I have seen Tesla charging stations in towns along the interstate. This one was in Lovelock, NV. It was co-located with a Chevron station.



I saw another one in Grand Junction, CO.

 

[GRG55]

In the car market solutions are appearing. Within the past month I have seen Tesla charging stations in towns along the interstate. This one was in Lovelock, NV. It was co-located with a Chevron station.

I saw another one in Grand Junction, CO.

I am not a big fan of Elon Musk or Tesla, but he should get full credit for importing from the tech industry a higher level of showmanship and marketing to cars.

Tesla continues to systematically address and try to overcome each issue or objection that is raised against electrics. Early on, before the introduction of the Model S, they took a Tesla Roadster across the country coast-to-coast, just to prove it could be done (however inconveniently). The Supercharger station highway network was the next step to address range anxiety (every guy's nightmare - not being able to go the distance ).

I see Model S sedans around my city during my commute. Have a friend with a weekend home in the mountains an hour to the west. There's 3 Tesla Supercharger stations in the laneway behind his mountain chalet. He's never seen a car using one of them yet. The prospect of using a Model S in a winter climate with cabin heat, windshield defrost, lights and wipers all reducing the already limited range seems to lose out to GMC Yukons and Ford Explorers in that application.

 

[Everskyward]

I am not so much a car fan that I would recognize a Tesla on sight. I was startled enough by this charging station that I took a photo, though...

No one was using any of the bays. But then I was the only one at the pumps. It's Lovelock, NV, after all.

I won't consider an electric car until they come in AWD or I live in a place where one is not needed.

 

[Jimmy cooper]

In the history of aviation has any new technology "saved" General Aviation? IMHO, no.
In the history of aviation has any technology improved General Aviation? IMHO, yes.
In the history of aviation has the government managed to screw up gains made by General Aviation? IMHO, every time.

What will save GA is the return of a healthy , industrious middle class. They were,in the seventys and eightys, at the height of aircraft production, the ones who purchased light aircraft. Since then, with good paying jobs leaving this country for cheap labor destinations , aircraft in the US is practically non existent. The " govmint" would naturally be envolved in any electric aircraft as they have been in any worthwhile advance in our history, including the Internet which govt. Funded Scientists invented.

 

[Shepherd]

Hmmm. Thought they used these for the Apollo missions.

Isn't it strange?
We have had closed fuel cell systems since the mid 1960's, but everyone acts like the technology never existed. I built a closed system back in the 1987, for something to do between projects. I talked to one of my (former) guys a few weeks ago. It's still running on the same gallon of water I originally put into it. The clock it drives has had to be replaced three times.
The biggest issue is creating enough hydrogen to be useful, but strides have been made, just ignored.

 

[N659HB]

I see us moving to electricity for most propulsion, eventually, but nothing will happen until there is a breakthrough in battery technology. Perhaps there's an as-yet undiscovered natural element that will solve the puzzle. BTW, didn't Tesla once envision aircraft powered by induction of "free" electricity?

 

[172andyou]

Solar power will not save GA.

There is, however, an outside chance that solar power may be able to save itself. It's been teetering on the edge of extinction since the 70s, even with massive infusions of government funding.

And "outside chance"? Solar power is already cost competitive with fossil fuels if you take into account the enormous infusions of government funding the fossil fuel industry gets. It's only going to get better from here. Solar has storage issues, thanks to there being darkness at night, but otherwise the battle is already over and solar won the battle for homes and most businesses.

Storage density, that's the holy grail that will allow it to win for everything.

 

[NHWannabe]

And "outside chance"? Solar power is already cost competitive with fossil fuels if you take into account the enormous infusions of government funding the fossil fuel industry gets. It's only going to get better from here. Solar has storage issues, thanks to there being darkness at night, but otherwise the battle is already over and solar won the battle for homes and most businesses.

Storage density, that's the holy grail that will allow it to win for everything.

I'm not against solar but please point out how solar is cost competitive with fossil fuels and side by side comparison of subsidies. Let's not forget that forcing utilities to purchase power from homeowners at retail drives up the cost of electricity for all of us who don't have solar. I doubt that the residential market would be as viable if utilities were paying wholesale prices to homeowners.

 

[Sundancer]

Fuel costs are only one variable. Listen to the tone in the OP. It's coming from a generation of people that are going to have as much influence reshaping our world as we Boomers did starting in the 1960s.

If we want to attract the next generation of potential pilots into GA in any quantity we aren't going to do it with clapped out 172s and Cherokees, or even with Rotax powered LSAs.

People don't buy $5000 bicycles or $100,000 Teslas because gasoline is expensive. Many (Most?) of them are attracted by the perception the bike or the Model S is a technology platform more advanced than the alternatives. I can see an electric airplane creating a similar reaction.

The homebuilt movement went from a bunch of guys gluing wood ribs and covering the result with fabric to hot wired foam and composites & CNC matched hole drilling in aluminum. Those advances attracted a lot of people into the movement. LSAs have helped the commercially produced light plane GA market stay alive, but it needs to do something more to have a vibrant future.

 

[Sundancer]

I do get the "newest toy" impulse; we also remember plenty of extinct lines and blind alleys. Some lead to variations that suceeded, true enough. But I can't find my PDA or CD player, either. . .

"Gee whiz" will attract some small sub-set; of that group, a smaller set will continue in GA. At the price points that will probably prevail, that quite small group, with the disposal income and interest (think Cirrus buyers), will come aboard. Electric airplanes may increase that number. Slightly. The fleet will shrink, and the newer aircraft, with much higher values, will make up a bigger chunk of a declining total number.

But flying has just a remnant of it's former mass appeal; it ain't the thing anymore. And of those it attracts, the highly, highly risk adverse make up a larger and larger percentage. Electric or recip won't be that much of a factorr in saving GA. New aircraft will be much safer for the bulk of pilots, and boring as church for the rest of us.

Just my opinion. I could be wrong.

 

[bflynn]

The idea is interesting. But right now it isn't even remotely feasible without energy storage mediums that perform at much better storage/weight capacities.
....

This and the rest that I removed for brevity. MOT, the technology is not there yet to enable wide spread electric flight. Extending it, solar cells do not generate nearly enough electricity to sustain flight on any production aircraft.

Electric airplanes are an exciting idea but they're just not practical for most missions yet. You have to hunt quite a while to learn that the Sun Flyer RX1E only has 40 minute of endurance. Adding in mandated FAA reserves, you can basically fly around the pattern once or twice very quietly.

 

[SkyDog58]

No, electric planes will not save GA. What will is big loud radial engines and cheap gas.

 

[GRG55]

Isn't it strange?
We have had closed fuel cell systems since the mid 1960's, but everyone acts like the technology never existed. I built a closed system back in the 1987, for something to do between projects. I talked to one of my (former) guys a few weeks ago. It's still running on the same gallon of water I originally put into it. The clock it drives has had to be replaced three times.
The biggest issue is creating enough hydrogen to be useful, but strides have been made, just ignored.

This is where I am sceptical - the hydrogen sourcing. Right now this is the expensive problem that has not yet been satisfactorily solved (because if it had we would be using fuel cells everywhere). Like California the west coast of Canada prides itself as an environmental leader. The City of Vancouver (Canada) and the town of Whistler, B.C. bought and put in service buses powered by the Ballard Power Systems fuel cells as a "green energy showcase" just prior to the 2010 Winter Olympics that were held in those two venues. The closest source of hydrogen is in Quebec. The hydrogen is hauled by truck from source to the west coast in tube trailers. The trucks use diesel. The amount of diesel energy consumed to deliver the fuel is more than the energy in the hydrogen payload being hauled. Hard to make a credible claim this is "environmentally friendly" in that circumstance, non? After half a decade of subsidies the buses are being retired and replaced with...wait for it...diesel buses.

I am sure every one of us here wants a cleaner environment and a "sustainable" economy (when someone figures out what that really is please share it with the rest of us). But the political hype around the evils of carbon, the "hydrogen highway", "renewable" energy and the ever present need for our politicians to gain a "green economy" photop is getting in the way of intelligent, fact based public discourse. How on earth can our governments justify the major subsidies that purchasers of $100,000 Teslas are eligible to collect from the rest of us? Really...

 

[ircphoenix]

The reality is, for all their evil, fossil fuels are FANTASTIC energy sources. They have very high energy density compared to other sources. And until we find a way to store 'free' energy in a competitive energy dense container, fossil fuels will continue to be burned for on demand power.

Fossil fuels aren't so heavily relied upon necessarily because they're easy (they are, but getting more difficult to extract)... they are, in fact, excellent sources of energy.

 

[Sundancer]

Yep, fossil is the way to go for now- so much energy in such a small mass; think about pouring a gallon of water from you car window, slowly enough that you travel 35 miles before the jug is empty; that's a "thread" so thin you could barely see it. My Mazda is getting about 35-36 miles per gallon.

Solar is cool, but, like recycling plastic, is more politics than practical, with dome narrow niche utility only.

 

[Hank S]

I am not so much a car fan that I would recognize a Tesla on sight. I was startled enough by this charging station that I took a photo, though...

No one was using any of the bays. But then I was the only one at the pumps. It's Lovelock, NV, after all.

I won't consider an electric car until they come in AWD or I live in a place where one is not needed.

I won't consider an electric car until range is several hundred miles and it can recharge in five minutes. Until then, I'll drive my gasoline-powered car several hundred miles and pump another tank of gas in five minutes and drive on, while the electric cars line up to sit for several hours recharging.

 

[172andyou]

I'm not against solar but please point out how solar is cost competitive with fossil fuels and side by side comparison of subsidies. Let's not forget that forcing utilities to purchase power from homeowners at retail drives up the cost of electricity for all of us who don't have solar. I doubt that the residential market would be as viable if utilities were paying wholesale prices to homeowners.

The IMF estimates that fossil fuels are subsidized internationally at a rate of something like $10M per minute. Here's there recent report on the subject.

If you want side by side, you'll have to assemble it yourself. The renewable subsidies are well documented.

http://www.imf.org/external/pubs/ft/wp/2015/wp15105.pdf

The key findings of the study are the following:
 Post-tax energy subsidies are dramatically higher than previously estimated—$4.9 trillion (6.5 percent of global GDP) in 2013, and projected to reach $5.3 trillion (6.5 percent of global GDP) in 2015.
 Post-tax subsidies are large and pervasive in both advanced and developing economies and among oil-producing and non-oil-producing countries alike. But these subsidies are especially large (about 13–18 percent) relative to GDP in Emerging and Developing Asia, the Middle East, North Africa, and Pakistan (MENAP), and the Commonwealth of Independent States (CIS).
 Among different energy products, coal accounts for the biggest subsidies, given its high environmental damage and because (unlike for road fuels) no country imposes meaningful excises on its consumption.
 Most energy subsidies arise from the failure to adequately charge for the cost of domestic environmental damage—only about one-quarter of the total is from climate change—so unilateral reform of energy subsidies is mostly in countries’ own interests, although global coordination could strengthen such efforts.
 The fiscal, environmental, and welfare impacts of energy subsidy reform are potentially enormous. Eliminating post-tax subsidies in 2015 could raise government revenue by $2.9 trillion (3.6 percent of global GDP), cut global CO2 emissions by more than 20 percent, and cut pre-mature air pollution deaths by more than half. After allowing for the higher energy costs faced by consumers, this action would raise global economic welfare by $1.8 trillion (2.2 percent of global GDP).