So somewhere somebody discovers a method to generate say 15kW from a small handheld cube. Quantumfluctuating strings in a darkmatterfield 
but basically safe and limitless.
The inventor decides not to make money of it and sells it for an affordable price. I don’t know, something like a midsized car at first but drops down to the price a new pc.
What would happen to the economy, will it see a growth because of this invention or opposite? Would all powercompanies go out of business?
Tesla claimed he had a way to make energy limitless and free. J.P. Morgan had financed his efforts for a while and he had a mad laboratory in Colorado Springs where he shot bolts of electricity at the sky. How completely awesome. He did invent some pretty terrific things like finalizing the manifestation of alternating current. I tend to believe he had something going on there - and he died completely broke and ignored at that point. Whether he did or not, I don’t think the powers that be would easily allow that kind of technology happen without putting up a good fight. Yeah, for sure you would put people out of business and take mad dollars away from a lot of folks. I think it’s similar to the way the internet is being challenged as a free commodity. I’ve also heard spook stories of inventors being shut down because their area of study was so compelling, it compromised national security and the government got involved. I am trying to remember that source, but I’m frozen right now. I just think that technology has always been highly prized and possibly regulated by people who may stand to lose from free energy.
I would assume the following would happen (over a timeline of maybe 2-3 decades)
Pretty much all cars are designed to run on these cubes, starting with retrofit kits
Africa experiences a rapid growth in their energy consumption and ability to industrialize if they do not need to build an electricity grid and can make all their energy locally
In the west, people see the same standard of living as before but with lower costs
Climate change is largely halted, as is pollution from coal
I don’t think it’ll make that big a difference in the west. Granted people will power their autos and homes with it, and with average household energy expenses of about $5000 a year (gasoline, electricity, natural gas, etc) it will lead to a higher standard of living. That 5k will now be spent on other things. However I don’t know what net benefit that will have to the economy.
I would foresee an explosion of “gizmos” – beyond what we have now, which is already surpassing remarkable. I think real robots would not be very long in coming.
Also…it wouldn’t be long before some ratbag came up with a way to weaponize it.
There’s so much more than the $5000. Air transport is revolutionized. Individual air transportation becomes feasible and affordable. Water shortages in all kinds of coastal areas disappear (and are replaced by brine problems in those coastal waters). Deserts would bloom - that is, all kinds of areas will be developed that are uninhabitable now. Hell, even space exploration becomes much more feasible.
Heat pollution might start to be a worry. Light pollution certainly would run rampant.
But yeah. Flying cars.
Due to increasing standards of living the demand for high tech metals and meat would skyrocket. Society becomes more decentralized and more reliable since you never have to worry about the grid going down. Less of certain types of pollution, much more of others. Someone would make a sex toy out of it.
I’m bad at math and rocket science, but could you string a ton of these together and make some sort of neato propulsion system? Or would it be about the same as what we have now?
Free energy is pretty much the way to every utopian science fiction scenario ever. It’s the biggest, silliest magic wand in the book. Food and water become cheaper and more plentiful, transportation costs become essentially nil (further reducing the costs and increasing the availability of food and water), manufacturing becomes ludicrously cheaper. Poverty is eliminated. Most pollution disappears. Space travel becomes viable.
Remove power needs and you remove every technological bottleneck there is, and damn near all the sociopolitical ones. It’s magic.
Since we’re talking about magic, why not? And we’ll need to; without having to worry about food, water, or fossil fuels, we’ll need to harvest the belt for rare metals relatively soon. But we’d certainly find a way.
Now add in the energy costs of making and moving everything you buy or use. If you follow the moneytrails backwards, a huge percentage of your purchase cost of things in general comes down to energy.
The cost of a lot of foods would be slashed. I bet the quality of fresh product and meat would increase. No need to breed for durability and harvest early when you can fly everything from the field to the table instead of using boats.
(That, and I could own less sweaters, since heating my house to say 75° would be more affordable))
No more droughts. Lack of water can be solved by energy, since the oceans are nearly limitless sources of water on a human-use scale. Desalination becomes nearly free, and because transportation is mostly an energy problem too, transporting into desert areas becomes nearly free too. The Sahara and other deserts can bloom.
Huge economic benefits to the third world, as access to clean water and water for farming is no longer an issue. Life expectancy goes way up for big chunks of the world.
Yep, as life expectancy rises, so would use of natural resources. The problem with making anything better for humanity will always be our inability to control the population. Until people would be willing to say these people can have children, and or, I accept euthanasia as a viable concept, I’m not sure we’d see any improvement in the quality of life. There would be huge advances that promote proliferation of the population and the back-blow would be palpable.
Sure, population becomes an issue, eventually…but the planetary carrying capacity becomes much higher as well. Eventually we’ll need to implement global population control standards, likely at gunpoint. But not for several generations.
My wife stops nagging me about leaving lights on.
Also, many foods wouldn’t even need to be flown in. I imagine that vertical farming would really take off when electricity and fresh water (and various manufacturing processes) become much cheaper. Picture a grocery store with several floors of grow-op style greenhouses supplying produce on-site. Fruits and vegetables could be picked on the same day they’re sold, and delivered by freight elevator rather than by ship.
The world disappears in a puff of free unlimited energy.
How many people around the world have jobs that involve the creation of energy? Coal, hydro, nuclear, petro, natural gas, wind, solar-a massive shut down for these businesses and the businesses that support them. The automotive industry might grow because, with a new power source that weighs next to nothing and has no emissions, there’s no reason to limit the size of vehicles, and no reason not to drive everywhere, cluttering up the highways even more than they are today.
Well, steam engines that only ever need topping up with water would be one possibility for travel along the ground (although electric motors might be simpler).
For flight, ducted electric fans could provide propulsion - and maybe we could have airships where the buoyancy is provided by hot air (if heating it is free), rather than helium or hydrogen.
Propulsion outside the Earth’s atmosphere would still require a propellant, but if you have essentially unlimited power to apply to the job of squirting it out, this would be a big deal.
Earlier related thread (“Economic consequences of a new, cheap, safe, ‘infinitely available’, energy source”).
What does each cube weigh?
Heat pollution wouldn’t be an immediate issue – the direct thermal output of energy use would be much less than what we have now (the same direct thermal output plus greenhouse gas effects). Light pollution might increase, though I’m not sure it would be any more of an issue than it would be anyway with increases in lighting efficiency from the transition from incandescents to CFLs to LEDs.
As for flying cars, the real bottlenecks are likely to be mechanical (if your rolling car fails suddenly, you stop; if your flying car fails suddenly, you fall) and human (I see enough people who can’t handle two dimensions, much less three).