High-Level Project Summary
It is important that energy can be stored on Venus for space exploration missions, as its acidic, boiling hot 475°C atmosphere, renders currently available batteries useless. Our solution solves these problems, using a tethered aerostat, equiped with solar panels and a microwave power beaming transmitter to produce enough useable power that a surface lander and/or rover mission using high temperature electronics could operate without battery storage, or if batteries were needed for peak instrument power they could be protected with existing cooling and pressure vessel technology.
Link to Final Project
Link to Project "Demo"
Detailed Project Description
As the closest planet to Earth (being 3.69 times closer to Earth on average than Mars), the exploration of the surface of Venus is one of the most tangible goals for interplanetary exploration. Moreover, it has been posited that, although the current climate is particularly harsh, the climate of Venus was once similar to that of Earth before being enveloped by greenhouse gases, and thus presents an opportunity to study the effects of greenhouse gases and climate change. The exploration of Venus' surface is therefore of high precedence in terms of space exploration.
The problem however, is that due to the extreme temperatures and pressures, previous missions to Venus' surface have been very short lived as power sources and electronic equipment failed from overheating.
Our solution proposes to circumvent this issue by instead putting the primary power source in the upper toposphere, around 60-70 km above the surface of Venus. In this region, NASA data indicates that temperature and pressure conditions are close to that of Earth's. Moreover, at this altitude, power sources will be above the main cloud layer, and again, data from NASA has indicated that the efficiency of solar power absorption in this region has efficiency levels of close to 90% due to the lack of interference from cloud cover and magnetic fields. Therefore, it is feasible to implement a power source in this region by using an aerostat with solar panels to absorb radiation, with the absorbed solar energy then being transmitted to the ground base or even rover directly through radio transmission.
The aerostat gas will be helium, which is bouyant under the composition of Venus' atmosphere, and will be enclosed by a Teflon-like skin similar to that used on the previous Venera missions. The aerostat will be tethered to the surface through a basalt fibre cable, which can withstand the pressure and temperature extremes, as well as the acidic conditions of the Venusian atmosphere. The solar energy will therefore be absorbed and re-transmitted to be used by exploratory craft either directly if a mission can be built that operates at the extreme temperatures, or for both cooling down and charging batteries housed within a protective enclosure.
Our approach therefore provides a solution to the problem of providing a durable, long term power source for multiple potential Venus surface explorations, by exploiting the properties of Venus' atmosphere to lift large loads above the clouds layer. We place our power source in the "safe zone" of the atmosphere, and reduce the need for producing a power source that must specifically withstand high pressure and temperature conditions.
Space Agency Data
'Surface temperatures on Venus are about 900 degrees Fahrenheit (475 degrees Celsius)'
'Venus surface pressure, then, appears to be more than 75 Earth atmospheres and surface temperature greater than 900 degrees F.'
'Venus has crushing air pressure at its surface – more than 90 times that of Earth – similar to the pressure you'd encounter a mile below the ocean on Earth.'
Hackathon Journey
Our team would describe the Space Apps experience as 'Inspiring', and 'awesome'. Our team was a mix, with more senior members, as well as new members, which was really beneficial for the learning experiences of all parties. Our approach to developing this project was relatively simple, we started out Saturday by researching multiple energy storage options, including mechanical springs, and dived quite deeply into battery technology researching molten salt batteries in particular. By the end of the day we had shifted focus, with the reliability figures we found in the current research not giving us confidence in the battery life lasting 60 days we shifted focus to finding other ways to store the power, which also lead to the inspiration of our aerostat, trying to find a way where we had more than enough power to just keep regular batteries cool using the technology we had seen in many research papers on Venus missions while studying the battery options. We changed our view. We discovered a material with enough strength to allow us to use a passive aerostat, allowing for a no moving parts solution, and after working out how much extra weight would be involved we shifted from using an electrical cable to carry power down the +60km tether to the ground, we modified the concept to use microwave power beaming to send the electrical power down to the mission on the ground, saving us weight and adding flexibility. We spent Sunday validating and checking our figures as well as researching the feasibility of sending a mission large enough to carry the cable weight to Venus before getting our presentation material ready for submission.
References
Parker Discovers Natural Radio Emission in Venus’ Atmosphere | NASA
The VEGA Venus Balloon Experiment (science.org)
NASA - Up, Up and Away -- To Venus
Progress Towards the Development of a Long-Lived Venus Lander Duplex System - Rodger W. Dyson and Geoffrey A. Bruder
Analysis of Solar Cell Efficiency for Venus Atmosphere and Surface Missions - Conference Paper · July 2013 DOI: 10.2514/6.2013-4028
High Altitude Venus Operational Concept (HAVOC): Proofs of Concept - Conference Paper · December 2015 DOI: 10.2514/6.2015-4545
Venus Rover Design Study - Conference Paper · September 2011 DOI: 10.2514/6.2011-7268
VENUS SURFACE PLATFORMS - White Paper for NASA 2021 Decadal Survey - Tibor Kremic, NASA, Glenn Research Center
VENUS SURFACE POWER AND COOLING SYSTEMS - Geoffrey A. Landis and Kenneth C. Mellott, NASA John Glenn Research Center
Venus atmospheric exploration by solar aircraft -Geoffrey A. Landis, Christopher LaMarre, Anthony Colozza
Venus surface power and cooling systems - Geoffrey A. Landis, Kenneth C. Mellott
Microwave and Millimeter Wave Power Beaming - IEEE Journal of Microwaves - DOI: 10.1109/JMW.2020.3033992
A review of Lighter-than-Air systems for exploring the atmosphere of Venus - K.M. Kiran Babu, Rajkumar S. Pant
Analysis of Solar Cell Efficiency for Venus Atmosphere and Surface Missions - 11th International Energy Conversion Engineering Conference - Geoffrey A. Landis, Emily Haag - DOI: 10.2514/6.2013-4028
Long-Lived Venus Lander Thermal Management System Design - 10th International Energy Conversion Engineering Conference - Rebecca Hay, Andrew Slippey, Calin Tarau and William Anderson
Combustion-based power source for Venus surface missions - Timothy F. Miller, Michael V. Paul, Steven R. Oleson
Power systems for Venus surface missions: A review, G.A. Landis, Acta Astronautica (2020), doi: https://doi.org/10.1016/j.actaastro.2020.09.030.
Long-duration Venus lander for seismic and atmospheric science Tibor Kremic, Richard Ghail, Martha Gilmore, Gary Hunter, Walter Kiefer, Sanjay Limaye, Michael Pauken, Carol Tolbert, Colin Wilson
Venus Surface Composition Constrained by Observation and Experiment - Martha Gilmore, Allan Treiman, Jörn Helbert, · Suzanne Smrekar - DOI 10.1007/s11214-017-0370-8
Progress Towards the Development of a Long-Lived Venus Lander Duplex System - Rodger W. Dyson and Geoffrey A. Bruder
Non-Cooled Power System for Venus Lander - Salazar, Denise & Landis, Geoffrey & Colozza, Anthony 10.2514/6.2014-3459.
Thermodynamic Analysis of a Cascade Refrigeration Cycle for Venus Lander Electronics Cooling Kevin R. Anderson, Thomas J. Gross, Christopher McNamara, Ariel Gatti - DOI: 10.2514/1.T5571
Miscellaneous Verena Lander Images - Surkov, Yu. A., et al., New data on the composition, structure, and properties of Venus rock obtained by Venera 13 and Venera 14, J. Geophys. Res., 89, 8393-8402, doi:10.1029/JB089iS02p0B393, Feb. 1984.
Naval research laboratory, Safe and Continuous Power Beaming – Microwave (SCOPE-M) demonstration - https://www.nrl.navy.mil/News-Media/Images/igphoto/2002980502/
Tags
#hardware #Venus #exploringOtherPlanets #aerostat #microwavePowerBeaming #basaltFiber