Off-world Power Generation Research
Current conclusions
- Use a satellite in low-earth sun-synchronous polar orbit.
- Use lasers for power transmission not microwaves.
- Use batteries for storage not capacitors.
- Use low-power laser handshaking for safety cutoff.
- Use best-practice cyber-security.
Power 101
Given
- Power is measured in Newton-meters per second or Joules per second or Watts.
- earth to moon: 238,900 miles
- there are four lagrange points that provide constant sun exposure at predictable locations
- l1 to earth/moon: 1 million miles
- A geosynchronous orbit takes one sidereal day, and is 35,786 km (22,236 mi) above the Earth's surface. Those closer to Earth orbit faster than Earth rotates, so from Earth, they appear to move eastward while those that orbit beyond geosynchronous distances appear to move westward.
- other interesting earth orbits: low goes across poles, medium used by GPS, high is slow and crawls west, Molniya spends more time away from equator; relative distances diagram
- the sun primarily produces visible light (not microwaves or gamma...)
- laser transmission is more efficient than microwave, except where earth's atmosphere interferes
- current status: A Gigawatt-range microwave system would weigh ~80,000 tons (prohibitively expensive) more lots more
- Solar cell efficiency
- Laser transmit antenna in space: 1 meter diameter per GW
- Receive: Several hundred meters across
Less likely premises
- <Earth> <-clearsky-burst-laser-- <L1 solar array>
- <Earth> <-microwave-- <Earth-orbit satellite> <-laser-- <Earth's moon> <-laser-- <L1 solar array>
- <Earth> <-clearsky-burst-laser-- <Earth's moon> <-laser-- <L1 solar array>
- <Earth-orbit satellite> <- <Earth's moon>
- <Earth's moon> <- <Earth-Sol Lagrange-point solar array>
Working Systems
NASA 2009 Power Beaming Competition
LaserMotive charging an unmanned drone
space elevator, and its power beaming need
- Attempting this challenge requires that the participating teams would excel at laser optics, photovoltaics, electrical and mechanical engineering, and overall system design. The vehicles must be lightweight yet powerful. The laser beams must be well focused while tracking the climbers, and the climbers must be adept at converting them back into electricity and then into mechanical power. If you think this sounds complicated, you're right - out of about 40 teams that tried their hand at the challenge, only 3 made it to the final challenge.
Coupled PV cells and Lasers
Often called Power Over Fiber.
MH GoPower (MHGP) produces a high-performance silicon-based vertical multijunction (VMJ) PV cell that enables high-wattage laser power transmission. See here.
Preliminary test data is shown for a 0.78 cm/sup 2/ VMJ cell with 40 series connected junctions producing 31.8 watts at 25.5 volts at near 2500 suns AM1.5 intensity (40.4 watts per cm/sup 2/ output at 211 watts per cm/sup 2/ input with an estimated efficiency near 20%).
Powerlight has free-space power beaming tech. LaserMotive has previously demonstrated power beaming systems with a receiver-specific power as high as 800 W/kg.
Solar Panels
Why not buy a nice full-sized panel and see what we can collect with it?
330W for $271 ($.78/W)
100W for $115 ($1.15/W) (bought)
Panels and battery setup
Someone used the Renogy panel to charge their RV, "My system consists of the following main components:"
2 - Victron Multiplus 12/3000/120-50 Victron Blue Solar charge controller MPPT 150/85 15 - 100 watt Renogy solar panels Victron Color control gx Victron BMV-702 battery monitor 4 - 1000Ah LifePO4 Winston battery cells
Here's 3.3kwhr in a suitcase using "18650"s.
Jehu, my fave instagram electric ride hacker, explains how to build your own powerwall. I need this.
Super capacitors
- Super-capacitors are not ready to outperform batteries, at least not yet.
- Because existing supercapacitors have poor energy density per kilogramme (currently around one twentieth of existing battery technology), they have been unable to compete with conventional battery energy storage.
- Even with this restriction, supercapacitor buses are already being used in China, but the current technology means that they need to stop to be recharged frequently (i.e. at almost every bus-stop).
- Demonstration of using a supercapacitor to meet the needs of charging a car, definitely within its ability. Electroboom agrees.
Small Lab Research
We should be able to set up two arduinos or pis, one receiving sun solar to power a laser, and another receiving laser solar to power a battery. We have a lot to learn about basic electrical wiring and arduinos and pis.
A hackster laser morse code transmitter and receiver setup, very useful The laser that was used, very popular, didn't find any others yet
There are lots of competing low-quality solar+battery projects, where's the winner? Still looking...
- this does it all, with pi webserver and arduino to monitor power, but doesn't give many details
- expensive adafruit gear
- might be good but where are the docs?
- work-in-progress but describes pulsed on-then-off to save power
General IoT research
- getting power to the stupid arduino
- open source power monitoring software and hardware using pi and arduido
- open source IoT SDK goo shit
Strong lasers:
- Start with goggles, here's why
- 1-3.5W lasers "world's best" but not avail in US - does not seem to be easy to wire up, but perhaps we could crack it open
- 5W laser in lots of videos... but can you still get it anywhere?
- crazy styropyro's 200W "laser bazooka" - this guy is incredible, here's a diagram of him inverting a Galilean telescope to focus a laser - a short documentary - his ruby laser "my strongest ever"
- another ruby laser with detailed explanation
- found one! this guy's 3D printer laser hack is amazing, and linked to his laser part let's get it
Other random stuff:
Launching Payloads to Space
Rocket Lab’s Electron booster launches small satellites commercially
Nasa "Venture Class" contractors circa 2015
General Notes
Question: what's the maximum input into a photovoltaic cell? Exposing it to the sun in space will provide what percentage of peak opportunity? Should we employ mirrors or prisms to redirect more sunlight into the PV cells? what would be most cost effective: adding more PV cells or adding redirected/reflected sunlight to existing PV cells?
Wikipedia: Wireless_power_transfer via laser (aka "Power Beaming")
Wikipedia: Space Based Solar Power (SBSP)
Long Range Wireless Power by Wi-Charge demoed at CES 2018 - First wireless power system using lasers for consumer applications. Complies with mandatory IEC 60825 sagfety standards for consumer use.
OEM looking to incorporate wireless power modules into new products? Apply for beta
NASA Armstrong Fact Sheet: Beamed Laser Power for UAVs
Power by Light - blog with working prototypes
Youtube: Wirelessly Powered Train
Youtube: Photovoltaic laser power converters with increased voltage output (27m)
Academic Papers
U.S. Energy Department’s own Lawrence Livermore National Laboratory (LLNL) 2009 proposal (PDF)
Paper: Design and optimization of GaAs photovoltaic converter for laser power beaming
Paper: Photovoltaic laser power converters for wireless optical power supply of sensor systems
Paper: High-Voltage GaAs Photovoltaic Laser Power Converters
Youtube infotainment
- electronics: jehugarcia, ElectroBOOM, GreatScott!, EEVBlog, bigclivedotcom, Jeremy Fielding, Fran Blanche, The Hacksmith
- lasers: styropyro, Marco Reps
- robotics: Metatronics, Adafruit Industries, simone Giertz (relentlessly pursues creativity with fun robots)
- other: Captain Disillusion (awesome entertaining video 3D graphics), Cody'sLab (chemistry), AvE (mechanical engineering (and electronics?)), PhysicsGirl (physics)
- general: The King of Random, TheBackyardScientist, SmarterEveryDay, Veritasium, Vsauce, Adam Savage’s Tested