Types of Energy Sources Used to Power Space Missions
Satellites, spacecraft, telescopes, lunar orbiters, etc., are all the end products of incredibly large-scale space missions. And a lot is invested in the form of financial, intellectual, and natural resources to initiate and sustain all kinds of space missions aimed to aid humanity.
Rightly so, with the expansion of space-based technology and its myriad benefits, human dependency on related services has increased significantly. For instance, as the satellite ecosystem grows stronger and becomes more advanced in space, it enables the development of higher-level of communication on Earth in the form of fourth-generation (4G) and fifth-generation (5G) technologies.
Today, these technologies serve various purposes such as Earth observation, communication, navigation, weather forecasting, space telescopes, space science, and human space exploration. These technological developments have placed high demands on space power supply systems as they play a crucial role in sustaining various space missions in harsh conditions throughout the projected time duration.
However, current state-of-the-art power systems are too large, bulky, or inefficient for future space missions, and some are unable to operate in harsh environments. The rapidly growing space technologies are resulting in the rising need for new materials to reduce the mass of space power systems. Understanding the performance requirements of space power subsystems for various applications is critical for material procurement.
Hence, there is huge traction toward the development of power systems with significant mass and volume reductions, increased efficiency, and capability for operation across a broad temperature range and in intense radiation environments to meet future requirements.
Due to its various applications and benefits, the demand for space technologies has increased. In addition to this, several emerging players, along with established players operating in the space power supply market, are continuously working to develop lightweight and cost-effective space power supply solutions.
According to the BIS research market report, the global space power supply market is estimated to reach $5.176 billion in 2032 from $2.62 billion in 2021, at a growth rate of 1.66% during the forecast period.
Three Major Energy Sources Used in Space Power Systems
In a space mission, electrical power is essential to operate instruments as well as to support equipment. There are various power requirements in a space mission, such as computing, communications, sensing electronics, and propulsion. Significant peak power levels are necessary to allow the radars to achieve a better range or penetration through materials and to improve the efficiency of the working equipment. Efficient energy sources are required to generate such a huge amount of electrical power. A few of those energy sources are discussed as follows.
1. Solar Power - The sun provides around 1.4 kilowatts of power per square meter of the Earth's orbit and proves to be the most efficient resource for the spacecraft power system. This has led to the use of solar as the predominant method for generating power for satellites. The effectiveness of solar panels is determined by the temperature, intensity, and angle at which the sun's rays strike them. ?
For instance, the Mars Exploration Rovers obtained all their electrical power from solar panels. There was concern early in the mission that the sustainability of the rovers would be lowered due to dust accumulation, but the dust was removed by wind over time. The lifetime of the rovers would be limited by dust accumulating on the rovers, but the dust was periodically removed by wind, leaving mechanical failure as the only limiting factor in the rovers' lifetimes. ?
领英推荐
However, many satellite missions require alternative power sources, such as lithium-ion (Li-ion) batteries, to operate in extreme environments. These energy storage systems allow satellites to operate in deep space missions far from the sun or during periods when they are moved out of the sun into the shadow of the Earth, preventing solar panels from generating electricity.
?
2. Nuclear Power - Missions that require traveling a long distance from the sun often use radioisotope thermoelectric generators (RTGs). These devices contain radioactive material such as Plutonium which produces heat from radioactive decay. Later, this heat is converted into electric power. RTGs consist of a fuel cell, thermocouples, and shielding. The efficiency of an RTG decreases over time due to decay of the heat source and degradation of the semiconductor thermocouples from radiation.?
The main advantage of an RTG over solar power is that the RTG can work in a harsh environment, away from the sun for a very long time. For instance, the Voyager probes, currently the most distant artificial objects, are both powered by RTGs and are still operating, even with the loss of some instruments.??
Due to the presence of radioactive material in an RTG, safety is a major concern while designing the power system. Modern RTGs are designed to survive a launch failure or re-entry without dispersing their fuel. For instance, Apollo missions 12-17 carried an RTG as part of an experiment in which it had been left on the moon, but one fell on Earth during the return of Apollo 13. This RTG fell into a deep trench in the Pacific Ocean and is believed to be currently intact.
?
3. Fuel-Cell Sources - For decades, hydrogen gas has been used as a fuel for space missions. Hydrogen-oxygen fuel cells combine these two chemical components at a controlled rate to produce heat, electricity, and some chemical waste product. One of the advantages of the hydrogen-oxygen fuel cells is that the waste produced by the reaction is water, which could be used by the crew.
Like RGTs, Fuel cells also have the advantage of functioning sunlight, but the fuel in a fuel cell may deplete its fuel supply in days of operation. However, safer materials are used in fuel cells, and their reaction rate can be controlled to limit waste heat. The poor energy-to-mass ratio of fuel cell systems may limit their applicability to near-Earth manned spacecraft, where a supply of oxygen is already needed, and the wastewater can be used.
?
Conclusion
In future space programs, power systems will be one of the essential components to be examined. The development of the space/launch vehicle's electrical power subsystem will have a significant impact on the space mission. All design characteristics must be carefully considered to build the correct combination of primary and secondary sources for the mission to perform in intense radiation and harsh environment.
Interested to know more about the growing technologies in your industry vertical? Get the latest market studies and insights from BIS Research. Connect with us at? [email protected]?to learn and understand more