Solar power requires space, is on 20% efficient, and costs thousands of dollars to install, forcing 80% of the world and most underdeveloped regions to rely on GHG emitting fossil fuels
The burning of fossil fuels generates 80% of the worlds energy however it accounts for more than 70% or 34 billion tonnes of greenhouse gas emissions annually$_1$ $_2$. Eco-friendly alternatives such as wind and solar power account for less than 15% of the total energy production as they are inefficient and rely on natural factors$_3$.
Solar panels for example, which account for 4% of America’s energy production, only harness 21% of the sun’s energy and doesn’t work when the sun is hidden, making the average solar panel generate less than half a kilowatt hour(a gas generator can produce upwards of 24 kWh)$_4$ $_5$ $_6$ $_7$.
To generate 6 kW(enough to power a home), solar panels can cost upwards of $12700, and for larger scale applications of solar energy, to produce 1 megawatt requires 6-8 acres of land or $890,000-$1,010,000. The prerequisite for land and money makes solar panels an unfeasible source of energy for many underdeveloped regions, forcing them to rely primarily on fossil fuels.
Governments worldwide are making an effort to switch over to renewable energy sources however to fully switch requires money and infrastructure. Many governments cannot afford this switch and as a result, they continue to endorse in the fossil fuel industries${10}$. Furthermore, a full switch requires public support, however many people don’t believe in climate change or are unwilling to change; there has been $4.3 Trillion invested in fossil fuels in 2024 and over 40% of Americans don’t believe in the need to deal with climate change${11}$ $_{12}$.
On Earth, the atmosphere, clouds, and other obstructions decrease the overall efficiency of solar panels when compared to space; in space, solar panels convert an average of 34% of the sun’s energy, however on Earth, they convert 21% of the sun’s energy$4$ ${13}$. Furthermore, in the space near Earth, the sunlight generates about 1360.8 W/m$^2$, however on the ground, less than half of this amount reaches the ground(on average only 300 watts reach the ground)${13}$ ${14}$ ${15}$. This means that on average, there is a 23.5% decrease in energy efficiency from space to Earth. To leverage this, many space agencies have been proposing to build a space based solar power system since the 1970s however not following through due to the high cost of development${16}$.
The ESA’s idea is to utilize a geosynchronous satellite(35,786 km) located above an array of rectennas, that utilize a special diode to convert electromagnetic waves into electricity. The satellite is equipped with 1 km$^2$ of solar panels that divert the electricity generated to a 2.45 GHz antenna that will send the energy to the ground rectennas in the form of an electromagnetic wave(Microwave or Infrared). The main issue with this plan and the reason why this system hasn’t been implemented yet is because of the cost to put a satellite into geosynchronous orbit is around $30,000 per kilogram. The total structure would be over a kilometer long, which could potentially take over 60 starship launches${27}$, which along with the ground infrastructure required, makes this plan too costly${17}$ $_{18}$.
Aetherflux is a company founded by Baiju Bhatt in 2024 with their own approach to space based solar power. Rather than using one satellite in geosynchronous orbit, Aetherflux plans to use a system of smaller satellites in Low Earth Orbit(LEO) to provide global energy coverage. These satellites will be integrated onto Apex satellite buses, a company dedicated to sending satellite payloads to space${19}$ ${20}$.
The problem with Aetherflux’s and ESA’s approach is the energy loss that occurs from their process: Sun > Solar Panel > Infrared Wave > Rectenna. A solar panel in space can convert on average 34% of the solar energy into electricity${13}$. When converting this electricity into an infrared wave, we are only able to convert about 25% of the energy${21}$. Finally, the rectenna can receive about 87.5% of the energy and distribute it. In total, this system is only about to retrieve ~7.4375% of the original energy.
A solar pump directly converts sunlight into a laser, removing the need for solar panels or antennas. It does this by first trapping and focusing the sunlight using a Luminescent Solar Concentrator(LSC), which is a Fluorescent plastic that traps light in from the faces and releases it from the edges. These edges are lined with Nd3+-doped silica fiber, a material that uses the excitement of Neodymium ions to generate a laser. When the concentrated sunlight hits the silica fiber, the atoms are excited and generate a high power infrared laser${22}$ ${23}$.