Power Plants on the Mars P/P/P : P roposals P ossibilities Szymon - PowerPoint PPT Presentation

Power Plants on the Mars P/P/P : P roposals P ossibilities Szymon Moliński Erasmus Brno P roblems 2013/2014 NELE Course

1. Proposals When we are talking about power plants on the other celestial bodies, like Mars, there are basic questions that we must answer. 1) Why we want this? 2) What types of powers stations Image: http://www.skin-artists.com could we use? 3) When we can do this?

Why we need Power Station on the surface of Mars? Automatic and robotic missions to Mars from one year to the next are bigger and much more complicated. Rovers, landers and in the future probably aircrafts need energy and power - solar panels mounted onboard are not the best of power supply to manned rovers, sample-return missions, mining and drill systems, life support systems and systems of producing fuel. They will need probably not hundred of Watts but kilowatts of energy to work.

MAXIMUM TYPE OF POWER MISSION ENERGY TIME OF WORKING SUPPLY PRODUCED RTG (Radioisotope Viking Landers Thermoelectric 30 W 1976-1982 Generator) Solar arrays Mars Pathfinder: (+ rechargeable 15 W 1997 Sojourner Rover batteries) Mars Exploration Solar arrays 140 W (only in Rovers: (+ rechargeable sol - martian 2004+ Opportunity batteries) day) Mars Science RTG (Radioisotope Laboratory: Thermoelectric 110 W 2012 + Curiosity Generator) Table: Mars missions and their power supplies.

Table from Wikipedia: Future mission to Mars under study. http://en.wikipedia.org/wiki/Exploration_of_Mars#Future_missions_2

What types of power stations will be the best? Overview of power generation options and energy pathways for Mars surface applications. Mars: Prospective Energy and Material Resources. Prof. Viorel Badescu. Springer 2009

Solar arrays and nuclear fission The comparison of surface solar energy utilisation and nuclear power generation shows that both technologies have advantages and disadvantages. A generally valid conclusion as to when either of the two approaches can or should be applied in Mars surface missions cannot be made. Both options have to be carefully evaluated for a specific mission profile, the technological availability and the broader Mars exploration plans. There will certainly be missions where surface solar energy utilisation is the technology of choice, and there will also be missions where a nuclear power system will perform very favourably. The compact, robust and reliable nuclear power sources generally are a hard match for surface solar energy utilisation in mobile applications and in high-power applications where a continuous supply with electrical energy is required day and night. Power System Options for Mars Surface Exploration: Past, Present and Future. Simon D. Fraser from: Mars: Prospective Energy and Material Resources. Prof. Viorel Badescu. Springer 2009

We have possibilities to build fission reactor or solar array power station on the surface of the Mars. There are other concepts: solar power plants on balloons or power sattellites in the Mars orbit. The technical solutions is not Image: http://www.3d-dreaming.com/2013/07/between-earth-and-sky-campus-landmark.html everything. Unappreciated issues are politics, culture and economy. Without them there will be no progress in the space power stations matter. Possibilities

Political Economical Technical Sociological Which countries want to Benefits. Efficiency of solar arrays. Space Race. achive this? Mars One and other Why they want to do this? Commercial uses. Robotics. confusing initiatives. Democcracy and Challenge for the Far East, exploration - merge is New industry sector. Material science. not the West? impossible? Experiences from Earth Nuclear energy in space... Power Stations. Experiences from space industry. The main issues connected to possibilities of construct power station on the Mars

Nuclear fission in space - developments • James E. Werner said that innovative fission technology for surface power applications is far different from the familiar terrestrial nuclear power stations, which sprawl over huge tracts of land and have large structures such as cooling towers. • “People would never recognize the fission power system as a nuclear power reactor,” said Werner. “The reactor itself may be about 1 ½ feet wide by 2 ½ feet high, about the size of a carry-on suitcase. There are no cooling towers. A fission power system is a compact, reliable, safe system that may be critical to the establishment of outposts or habitats on other planets. Fission power technology can be applied on Earth’s Moon, on Mars, or wherever NASA sees the need for continuous power.” The first nuclear power plants for settlements on the Moon & Mars, American Chemical Society, Press Release, August 28, 2011

Fuel cells on Mars There are many operational characteristics and design features inherent to fuel cell systems that make them an interesting option for a wide range of applications in space exploration. Fuel cells can be built from simple, repeating elements with few moving parts; this will make them highly reliable and long lasting even under harsh operating conditions. Fuel cells are very efficient; their superior fuel-to- electrical conversion efficiency will reduce mass and volume of power systems. Specific energy and energy density of fuel cell systems can be significantly higher than the design targets defined for future battery and flywheel energy storage systems. Mobile mission elements could thus be equipped with a full energy supply prior to launch from a Mars surface base instead of relying on battery recharging procedures during mission time, as it would be the case with a combined photovoltaic and secondary battery power system.

Solar Power Stations on Mars

On Mars, the insolation is reduced by the inverse squared Sun-Mars distance (about 1.5 AU) compared to the Earth insolation. Some studies indicated (Van Hemelrijck 1983) that the mean summer insolation on Mars lies between 150 W/m² and 240 W/m², out of about 600 W/m² of incident insolation. Using photovoltaic panels, this energy can be transformed into electricity; Photovoltaic panels currently convert about 15-25% (newest 40%) of sunlight into electricity. In addition, if DC/AC conversion is required, it would incur an additional energy penalty of 4-12%. The main disadvantage of using solar electricity on Mars surface is its limited power density, due to seasonal dust storms. So there is proposal to mitigate this deficiency by designing a balloon system for collecting solar electricity in the dust-free part of the atmosphere. This concept may be used to backup planned Martian power plants or as a primary energy sources where possible.

Problems If we want to build power station on Mars surface, we must spare with many problems. Costs. Average cost of launch 1 kg of material to Earth orbit (!) is 20,000 $. Technology of construction. Will we send all materials to the another planet or maybe we will use 3D printing from regolith? Who will build power station: automatic systems or humans? Weather. Dust storms on Mars, particles of galactic radiation, electrostatical charging of environment. Image: Max Planck Institute for Gravitational Physics

EMC Problems Energetic particles can ionise atoms and displace them within their crystalline lattice. For instance solar panels on spacecraft that leave the Earth’s atmosphere lose performance due to cumulative effects of displacement damages induced by energetic particles. A large solar energetic particle event can, within some days, cause the same degradation as an entire year of operation under the effect of only galactic cosmic rays. Ionisation is often the dominant mechanism by which the performance of on board electronics degrades. Mechanical and electrical insulating properties of teflon can also be changed when the material is irradiated to high levels, as well as painting used for thermal regulation. All this decreases the life time of the equipment.

Electrostatic charges The electrical activity present in the environment near the surfaces of Mars and the moon has very different origins and presents a challenge to manned and robotic planetary exploration missions. Mars is covered with a layer of dust that has been redistributed throughout the entire planet by global dust storms. Dust, levitated by these storms as well as by the frequent dust devils, is expected to be electrostatically charged due to the multiple grain collisions in the dust-laden atmosphere. Electrostatically charged dust has a large tendency to adhere to surfaces. NASA’s Mars exploration rovers have shown that atmospheric dust falling on solar panels can decrease their efficiency to the pointof rendering the rover unusable.

Dust storms Dust storms on Mars surface (and Dust Devils) are very common in martian summer. Clouds of electrostaticaly charged particles covers entire planet, solar arrays will be not usable in such place.

The End of introduction more detailed information will occur soon...