Space Based Solar Power practical project

[astralfx]

Hello,

I'm doing a project on SBSP and we have a few months to complete it, and in my written report I will be going over NASA's data they collected from their attempts. Calculating efficiencies and otheer variables between different stages of transmission, e.g. first from the sun radi to PV cells to generate electricity, then to power a microwave transmitter, which is beamed down to Earth taking into account gravity/atmosphere etc, then the receiver converting it back to electricity, then to AC/DC inverter. Talking about feasibility (launch cost, micro asteroids etc)

Okay so now I was talking to my lecturer, and I gave him an idea of me creating a scaled down version of the satellite (which will basically be 1 of the PV cells which would go in space), to a table top experiment, one I figure out the calculations in the written I can scale them down, thus get a high powered lamp or lamp's trying to replicate the sun's solar radiation. I'd also have a small microwave transmitter, transmitting the microwaves about 1-2m across to the receiver, with measuring equipment for voltage/current and microwave radiation during the stages. In the end, all my data scaled down should follow similar patterns if were in space, though not exactly, as it's more of a proof of concept

My supervisor told me I need to be a bit more detailed if we are to continue.

So aerospace engineers, anyone mind throwing some ideas around. I looked at NASA's data and their is a 0.4% energy loss with microwaave coming through the atmosphere, thus my idea is to just use a light material to account for that .4% loss and any gravitation effect in the form of refraction from the material for the microwave.

So yeah, just throw any ideas around for me for this project. I am thinking of enhanced chromium PV cells, anyone think of any else? Does my practical project sound reasonable to you, what microwave transmitter could I use? Am I missing anything in the theoretical part, I also had an idea from what I read on the net that I could use laser transmission instead. What's your take guys?

 

[berkeman]

Hello,

I'm doing a project on SBSP and we have a few months to complete it, and in my written report I will be going over NASA's data they collected from their attempts. Calculating efficiencies and otheer variables between different stages of transmission, e.g. first from the sun radi to PV cells to generate electricity, then to power a microwave transmitter, which is beamed down to Earth taking into account gravity/atmosphere etc, then the receiver converting it back to electricity, then to AC/DC inverter. Talking about feasibility (launch cost, micro asteroids etc)

Okay so now I was talking to my lecturer, and I gave him an idea of me creating a scaled down version of the satellite (which will basically be 1 of the PV cells which would go in space), to a table top experiment, one I figure out the calculations in the written I can scale them down, thus get a high powered lamp or lamp's trying to replicate the sun's solar radiation. I'd also have a small microwave transmitter, transmitting the microwaves about 1-2m across to the receiver, with measuring equipment for voltage/current and microwave radiation during the stages. In the end, all my data scaled down should follow similar patterns if were in space, though not exactly, as it's more of a proof of concept

My supervisor told me I need to be a bit more detailed if we are to continue.

So aerospace engineers, anyone mind throwing some ideas around. I looked at NASA's data and their is a 0.4% energy loss with microwaave coming through the atmosphere, thus my idea is to just use a light material to account for that .4% loss and any gravitation effect in the form of refraction from the material for the microwave.

So yeah, just throw any ideas around for me for this project. I am thinking of enhanced chromium PV cells, anyone think of any else? Does my practical project sound reasonable to you, what microwave transmitter could I use? Am I missing anything in the theoretical part, I also had an idea from what I read on the net that I could use laser transmission instead. What's your take guys?

Can you talk more about safety considerations for the microwave portion of your demo?

 

[astralfx]

Can you talk more about safety considerations for the microwave portion of your demo?

So my supervisor has fully accepted my project proposal. Great :D

Indeed I will discuss the effects of the microwave frequencies to be used on living creatures, such as birds, animals, and humans.

Any other thoughts?

 

[berkeman]

So my supervisor has fully accepted my project proposal. Great :D

Indeed I will discuss the effects of the microwave frequencies to be used on living creatures, such as birds, animals, and humans.

Any other thoughts?

Are you actually going to use microwaves in your demo?

 

[astralfx]

Are you actually going to use microwaves in your demo?

Of course. I can't use a giant microwave dish and antenna for obvious reasons. But I looked online for receivers and transmitters, problem is they are all products of sending actual data such as routers. I haven't done any calculations yet, but I don't think my power output from the a few PV cells will be too high.

Any ideas though for what I could us for this microwave generation.

 

[berkeman]

Of course. I can't use a giant microwave dish and antenna for obvious reasons. But I looked online for receivers and transmitters, problem is they are all products of sending actual data such as routers. I haven't done any calculations yet, but I don't think my power output from the a few PV cells will be too high.

Any ideas though for what I could us for this microwave generation.

Well, my point was that you should not be beaming microwaves across your science fair project, or else more than birds will be having problems.

You could simulate it with a solid state laser beam from a laser diode or laser pointer, hitting a simple photocell or PIN diode. You could use baby powder sprinkled in the beam path to show that energy is being transferred, and how when you block the beam with your hand, the output power goes away. Of course, the beam will only be 1mW or so, and the receiver circuit will be a simulation of power reception...

 

[etudiant]

There was a series of NASA symposia on Radiant Energy Conversion in Space run during the early 1980s, run at NASA Ames if I remember correctly. Afaik, they remain the state of the art in terms of space based solar power.
The studies showed that a solution to the problem of excess microwave energy from a solar power satellite was to transmit it via a phased array guided by a feedback from the ground. That way, if anything such an aircraft interfered with the signal received, the steering would be lost so the power beam immediately blooms widely, preventing any damage to the errant vehicle/people.
That aspect might actually be a more useful thing to demonstrate than the basic power beam.

 

[astralfx]

Well, my point was that you should not be beaming microwaves across your science fair project, or else more than birds will be having problems.

You could simulate it with a solid state laser beam from a laser diode or laser pointer, hitting a simple photocell or PIN diode. You could use baby powder sprinkled in the beam path to show that energy is being transferred, and how when you block the beam with your hand, the output power goes away. Of course, the beam will only be 1mW or so, and the receiver circuit will be a simulation of power reception...

Nice idea on using baby powder to visually display the transmission. Hmmm...

There was a series of NASA symposia on Radiant Energy Conversion in Space run during the early 1980s, run at NASA Ames if I remember correctly. Afaik, they remain the state of the art in terms of space based solar power.
The studies showed that a solution to the problem of excess microwave energy from a solar power satellite was to transmit it via a phased array guided by a feedback from the ground. That way, if anything such an aircraft interfered with the signal received, the steering would be lost so the power beam immediately blooms widely, preventing any damage to the errant vehicle/people.
That aspect might actually be a more useful thing to demonstrate than the basic power beam.

Interesting, I will definitely look into this and discuss it with my supervisor, as I have never heard about this "phased array" feedback. Mind linking the paper?