John Bucknell is CEO and founder of Virtus Solis, a company building the world’s first space-based solar power energy generation system to directly compete with conventional and renewable sources.
What was your professional journey to working in space-based solar power?
I’ve been around aerospace and space my entire life. My dad worked on NASA’s Apollo program. I have a photo of him standing in front of Apollo 11. I entered undergrad with the intention of being an aerospace engineer. When I graduated in 1995, Boeing was having problems and there weren’t any aerospace jobs.
I went to Detroit, took a role in automotive, and spent a dozen years learning about mass manufacture and energy systems. It gave me a deep appreciation for what it takes to make complex engineered devices that we all can afford. I left General Motors where I was deputy director of advanced propulsion in 2011 to join SpaceX. I was the first engineer responsible for the Raptor rocket engine which now powers the Starship vehicle. Elon Musk was looking at the SpaceX rocket engines and they all looked like hand-built crafts. He asked me to fix the rocket so that it was mass manufacturable.
I was the oldest person at SpaceX at the time, at age 40. The average age was about 28 and I lasted about 15 months before all my ideas that they thought were not aligned with SpaceX’s mission got me in enough trouble that I was let go. A dozen years later, they’ve done every single thing I told them to do. I joined another startup in Los Angeles called Divergent, whose goal was to radically improve manufacturing by lowering CapEx by eliminating dedicated tooling.
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What made you take the step back into the space field as a founder?
I wanted to spend the balance of my career doing something meaningful for the world. I wanted to do something about energy. If you look at the percentage of global GDP spent on energy, the periods of largest prosperity growth were in the 50s, 60s and 70s, when fossil fuels were really inexpensive. They only accounted for about between 3 and 6 percent of global GDP. In 2022 they’re about 14 percent. Those trends make it very challenging for everyone to get the energy they need. The market today is somewhere in the neighborhood of 8 to 10 terawatts of generation globally across all forms and it’s still 85 percent fossil fuels. If my goal is to make the world a better place, we need to solve energy.
I knew a little bit about this topic called space based solar power. It’s a 100-year-old idea that Isaac Asimov popularized in the short story “Reason” in 1943. The first engineering proposals were in 1968.
Everyone told me it doesn’t work and I wanted to know why. I ended up reading about 1,200 reports and I decided all the reasons why it didn’t work in the past were no longer true. NASA made a big effort in 1978-1980 and said they could make space solar power work and operational by 2006 at the cost of a trillion dollars. When they asked for it, Congress said they didn’t have that kind of money. There are still people at NASA today, 50 years later, who are angry about that.
The National Science Foundation wrote a postmortem about that decision and said it was rejected because the underlying technologies weren’t ready. They were going to have to build mines on the moon, factories in orbit, put habitats in space for the astronauts to put it all together. The space shuttle wasn’t flying yet. They would have to develop everything in space and build in-space infrastructure for the economics to work.
No one was making microelectronics at that time. Solar cells were 5 percent efficient. But they said in about 40 years the trends will probably converge. In 2018, SpaceX’s Falcon Heavy flew and microelectronics had become very inexpensive -, we had cheap compute. All of those things were there. We incorporated Virtus Solis in 2019 and have been on a path to build commercial systems ever since.
What else has changed that now makes the Virtus Solis tech possible?
All the electronics you need to make the systems work are now very inexpensive in the grand scheme of things. There’s many foundries globally, they’re cranking out millions of devices and the knock-on effect is having that low cost compute available. Robotic assembly, automated factories, all those things that allow you to put compute into manufacturing devices, allow you to build relatively complicated things with no human oversight.
It’s just a matter of determining how to best leverage that to get to the solution that gives us the answer we want. That’s what we’ve probably done better than everyone else in our vertical – we’ve designed a solution that allows us to undercut the cost of energy across the board in any market anywhere.
What are the advantages of using microwaves to transmit the energy from space as opposed to reflecting sunlight with mirrors to existing solar farms on earth?
Space-based solar power specifically involves collection of energy in orbit, which is the generation, and transmission of the energy to the ground, and conversion back to electricity. It’s a complete system. In space, it’s sunny all the time. The photovoltaics (PV) are more powerful in orbit because most of the ultraviolet radiation gets filtered out by the atmosphere. There’s about 40 percent more intensity of sunlight at the radius of Earth’s orbit. So with the same solar cell you get 40 percent more productivity.
On Earth, at high latitudes, there’s cloud cover for about three months of the year. If you look at the capacity factor, which is the percentage of time that a power plant makes its nameplate capacity, for solar, the best we get is about 30 percent. That’s sitting in a desert on the equator. Here in Michigan it’s about 18 percent. That’s just not enough to power civilization.
We use wavelengths that are about 3 centimeter-long microwaves to transmit to the ground. These can pass through clouds, rain, sleet, snow, dust with nearly no loss. The PVs are fairly well understood. It’s a solid-state device, you put it in orbit, it’ll generate energy all the time and then you can deliver it to the ground all the time.
These adjacent verticals that are either reflecting sunlight to earth or putting a laser to the ground, they don’t do anything for the wintertime and when it’s cloudy and rainy. They are sending light to existing solar on the ground meaning you can only serve existing customers. The are photons are the service. There’s a couple of startups doing that. Reflect Orbital is in low-earth orbit, which is a challenge because you’re still in the earth’s shadow about half the time. And you also are only in line of sight of a given spot on the ground because of the curvature of Earth like four minutes twice a day. So you have to have an enormous constellation to provide energy for any useful length of time.
If you look at the analyses, especially for Reflect or other solutions, it shows that diffraction is the curse of mirrors in space, that you end up with very low intensity of sunlight that reaches the photovoltaics on the ground. You need to have a large number of satellites all reflecting energy in the same spot to get the economics to work. If you’re building a constellation bigger than Starlink, it’s going to cost billions and billions and billions to build it. Then you have to recover those costs over 20, 30, 40 years.
It looks like you have relatively small satellites. Could you tell us a bit more about your system?
It’s just a thin panel that’s about one and a half meters across. It’s cover glass, then a layer of solar cells and a circuit board, effectively with power electronics, controls, then a layer with microwave antennas and another layer of cover glass. It puts out about 500 watts of radio frequency energy.
We’ll put up thousands of those satellites in massive arrays and as they get to about 500 megawatts or bigger, the vast majority of the energy that leaves the satellite arrives at the ground. So 500 megawatts, we get about 85 percent of the energy arriving at the receiver. For a 1,000 megawatts array and bigger, 100 percent effectively. So you’re able to get very good unit economics and use commercial launch to put up tens of thousands of those elements at a time. We’ll fly a small robot up with them whose job it is to take the stacked satellites out of the launch racks that integrate with the rocket and stick them together like Lego to make these very large arrays.
Our systems are half a kilometer to several kilometers across and the reason they need to be so large is to make a narrow beam so that all the energy transmitting arrives at the receiver. The intensity is only about a quarter of sunlight at the transmitter. You can’t really get any higher than that. So it’s very, very safe for people or otherwise. If you’re in a spaceship or an aircraft that manages to fly through the beam, which is unusual, any conductor reflects the microwaves away. So you’re safe and you’re not exposed. Safe, cheap, always available.
What would the receivers look like on the ground? Would they also have to be pretty large?
The element on the ground looks like a utility scale solar panel, except that there’s antennas on it instead of photovoltaics. They’re built the same way as a solar farm – you get the same land, the same inverters, the same solar trackers, the same grid connection. Any solar developer can build the ground station.
They have about a 2 kilometer fence line – roughly 400 acres – which is about the same size as a 400 megawatt solar farm. We can put up to 1,500 megawatts in the same spot. So about four times smaller than an equivalent solar farm.
Do you have plans to do an in-space demonstration in the near future?
We’re going to fly a pilot plant, which is a small scale operational power plant, in 2028. It’ll be a ground station probably in West Texas. It’ll be 100 kilowatts of power and that’ll be the last bit of technical risk to burn down. We expect to announce customer power plants for commissioning in 2030 sometime next year.
Could your system provide on-site energy generation for data centers or defense facilities?
It’s a little bit more expensive for military-use cases, but anywhere that the satellite has line of sight it can deliver energy to, which is about half the Earth’s surface for any given array. This means you can deliver energy anywhere, anytime, to anyone who needs it. It solves all the challenges we have with energy today. If you do it at low enough cost, you can undercut all the other solutions out there, which means you can scale, which is really the goal – to serve all of humanity, give all of us the energy we want. The Kardashev scale measures how much energy a civilization is able to produce, and for a Type 1 Civilization, that means powering everything from sunlight. We think that’s totally feasible.