How exactly would a solar power plant in space work?

JThe UK government is reportedly considering a £16 billion proposal to build a solar power plant in space.

Yes, you read that right. Space-based solar power is one of the technologies to feature in the government’s program Net Zero Innovation Portfolio. It has been identified as one potential solution, among others, to enable the UK to reach net zero by 2050.

But how would a solar power plant work in space? What are the advantages and disadvantages of this technology?

space solar energy is to collect solar energy in space and transfer it to Earth. Although the idea itself is not new, recent advances in technology have made this prospect more feasible.

The space-based solar power system uses a solar power satellite – a huge spacecraft equipped with solar panels. These panels generate electricity, which is then transmitted wirelessly to Earth through high frequency radio waves. A ground antenna, called a rectenna, is used to convert radio waves into electricity, which is then transmitted to the power grid.

A space solar power plant in orbit is lit by the sun 24 hours a day and could therefore produce electricity continuously. This is an advantage over terrestrial solar systems (systems on Earth), which can only generate electricity during the day and are dependent on the weather.

With global energy demand set to rise by nearly 50 percent By 2050, space-based solar power could be essential to meet growing demand from the global energy sector and combat global temperature rise.

Some Challenges

A space solar power plant is based on a modular design, where a large number of solar modules are assembled by robots in orbit. Transporting all of these into space is difficult, expensive and will have an impact on the environment.

This satellite would supply 2 GW of electricity to the United Kingdom. Although this is a substantial amount of energy, it is a small contribution to the UK’s generating capacity, which is around 76 GW.

the weight of solar panels was identified as an early challenge. But this was solved by the development of ultralight solar cells (a solar panel consists of smaller solar cells).

Space solar power is considered technically feasible primarily due to advances in key technologies including lightweight solar cells, wireless power transmission, and space robotics.

However, assembling just one of these solar power plants will require numerous space shuttle launches. Although space solar power is designed to reduce carbon emissions over the long term, there are significant emissions associated with space launches, as well as costs.

Space shuttles are currently not reusable, although companies like Space X are working to change that. Being able to reuse launch systems would significantly reduce overall costs.

If we manage to successfully build a space solar power plant, its operation also faces several practical challenges. The solar panels could be damaged by space debris. In addition, panels in space are not shielded by Earth’s atmosphere. Being exposed to more intense solar radiation means that they will deteriorate faster than those on Earth, which will reduce the power they are able to generate.

the Efficiency wireless power transmission is another issue. Transmitting power over great distances – in this case from a solar satellite in space to the ground – is difficult. Based on current technology, only a small fraction of the collected solar energy would reach Earth.

Lightweight solar cells make it easier to transport panels into space


Pilot projects are already underway

the Space solar energy project in the United States is developing high-efficiency solar cells as well as a conversion and transmission system optimized for use in space. United States Naval Research Laboratory tested a solar module and a power conversion system in space in 2020. Meanwhile, China has announced progress on its Bishan space solar power station, aiming to have a working system in space. 2035.

In the UK, a £16 billion (plus £1 billion in running costs) space-based solar power development is seen as a viable concept based on recent Frazer-Nash Consultation Report. The project is expected to start with small trials, leading to an operational solar power plant in 2040.

The solar satellite would be 1.7 km in diameter and weigh around 2,000 tonnes. The terrestrial antenna takes up a lot of space – about 6.7 km by 13 km. Given land use across the UK, it is more likely to be placed offshore.

This satellite would supply 2 GW of electricity to the United Kingdom. Although this is a substantial amount of energy, it is a small contribution to the UK’s generating capacity, which is about 76GW.

With extremely high initial costs and a slow return on investment, the project would require substantial government resources as well as investment from private companies.

But as technology advances, the cost of space launch and manufacturing will steadily decline. And the scale of the project will allow for mass manufacturing, which should bring costs down somewhat.

Whether space-based solar power can help us get to net zero by 2050 remains to be seen. Other technologies, like diverse and flexible energy storage, hydrogen, and the growth of renewable energy systems are better understood and can be more easily applied.

Despite the challenges, space solar power is a precursor to exciting research and development opportunities. In the future, technology is likely to play an important role in global energy supply.

Jovana Radulovic is Head of the School of Mechanical Engineering and Design at the University of Portsmouth. This article first appeared on The conversation.

Maria D. Ervin