Most people will agree that we need to find new sources of energy, as fossil fuel supplies gradually run out. But no-one has been able to suggest how renewable energy can provide our entire energy demands - until now.
Japanese engineering firm Shimizu has put together a plan to wrap the Moon in solar panels, which would harvest energy from the sun and transmit it to the Earth using microwaves and lasers, generating 'virtually inexhaustible' energy.
The ambitious plan would see the construction of a belt of solar panels 250 miles wide at the moon's equator. Antennae on the near side of the moon - that which always faces Earth - would then send the energy down to earth, to be picked up by microwave and laser receivers.
Shimizu estimates that the Luna Ring, as it has called the project, would produce the equivalent energy of burning 17 billion tonnes of oil. By comparison, China is estimated to use upwards of 2.3bn tonnes of oil equivalent (toe) every year. The International Energy Agency predicts that global demand will reach 17bn toe by 2030.
The plan would require a massive programme of lunar construction. According to Shimizu, many of the resources necessary would be found on the moon - it claims that ceramics, glass, oxygen, concrete and water could all be produced from lunar soil, along with the basic materials to build the solar panels.
Robots would be used to create the Luna Ring, running 24 hours a day under remote control from Earth, with support from a team of astronauts. The ring would include transport routes and would be studded with transmission facilities.
12 mile-wide antenna dishes would beam microwave power back to the UK, while smaller - but still very large - laser facilities would also be used. The main reason for the two types of power transmission would be to ensure power could continuously be received as the moon's position around the Earth varied.
Microwave power would be received by terrestrial 'rectennas' - large-scale arrays of antennae 2km across. Semiconductors and inverters would be used to convert the microwave power into electricity, which would then be supplied to the grid.
The laser beams from the moon would be aimed at offshore receivers, 1km wide and 500m across, which would house lenses similar to those found in lighthouses to focus the laser beam. Arrays of mirrors would be used to focus the beams onto photoelectric cells.
Laser power would also be used to convert sea water into hydrogen, through the high temperatures that it would generate. The offshore platforms would be allowed to float loosely, with the laser emitters on the moon capable of tracking their location. They would be situated around Earth's equator to take advantage of reduced cloud cover.
Such a plan would essentially form part of a global transformation to a 'hydrogen society', where the gas would be our major energy source. Hydrogen produces only water when burned.
The Shimizu plan calls for twenty years of further development before construction could begin on the Luna Ring, including more lunar exploration, lunar mining and the development of Space Solar Power Systems (SSPS). It estimates that the project could begin in 2035, but gives no prediction to how long it could take.
If you can't wait that long, take a look at the Kickstarter project currently being run by New Wave Energy UK. The Yorkshire-based startup is aiming to produce a proof-of-concept drone-powered solar array, which would hover above the earth at 15,000m. The energy would then be transmitted back to earth using wireless power transfer.
The advantages of being even that much closer to the sun would mean that a 500MW platform could pay for itself within 7 years. The platforms would be lifted by four drones, one at each corner, and would be able to move to avoid cloud cover. One advantage is that they would be able to provide power to disaster areas and hard-to-reach homes.
New Wave Energy is looking to raise £320,000 to cover prototyping, patents, research and simulations. It estimates that the whole project would cost £32million over five years. The team are working with researchers at Leeds and Cranfield universities.