Why can’t we amplify the temperature that solar panel receives from the sun to create more energy?
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Because it’s not the temperature that most solar panels react to, it’s the solar radiation.
If you were asking about solar thermal generation, then we can and do. Just google concentrating solar plant.
But PV solar panels need light, not heat.
Have you heard of a solar power tower?
Instead of collecting solar energy, the panels reflect and focus the energy to a central tower powering a steam turbine. There are newer materials used now, but the concept is the same.
There are also solar water heaters that collect the solar energy to supplement your home water heater.
As far as amplifying the temperature, first you would need to introduce another energy source to output the excess heat to amplify the temperature. This alone would create a massive loss of energy.
Then you would need someway to collect the excess heat. You can’t put a collector over the panels, you would block the solar energy coming from the sun. Then you would need to convert the heat to electricity. This is usually done by heading water until it turns to steam and moved through a turbine. You would need someway to focus the energy into the collector.
Even if you were able to bypass the amplification process and direct the energy right into the turbine system, you would still be losing energy during the conversion
I am no engineer but bringing cool water from underground to the back of the panels would set up a fairly big difference in temperature. That’s valuable for generating electricity, no? Granted pumping cool water is expensive.
Solar panels don’t use temperature to create energy, they use the actual photons coming off of the sun itself.
Light is made up of little particles called photons. These photons carry the energy that light has. When a photon hits a solar panel, it translates it’s energy into the movement of electrons that make up electricity. The rest of the energy gets converted into heat. The heat is a “waste” product and is not converted into usable electrical energy. In the most efficient solar panel designs, the amount of heat is actually minimized since that’s wasted energy.
Now, if you’re talking about using thermo-electric generators on the back of solar panels to capture some of that heat energy, it’s actually a good question to why we don’t do that. The reason is mostly because of cost-per-watt. The amount of “extra” energy you would capture from a solar panel using a thermo-electric generator would not outweigh the added cost that would come from doing that. A solar panel with added thermo-electric generators would cost more than one that didn’t, and the difference in cost would never be made up for by the difference in captured energy.
Solar thermal energy does exist. You take a bunch of mirrors, point them at a cylinder of water, they boil that water, and the steam turns a turbine.
Photovoltaic solar panels absorb too much of the sunlight to make this work, so they just have waste heat instead of useful heat.
The Sun emits a fixed amount of energy. This energy is distributed evenly in all directions. At the distance the Earth is from the Sun, there is around 1300 watts of energy, in the form of light, flowing through every square meter. You cannot get more energy than that. You can get less, if the panel is not perpendicular to the light rays (it depends on the hour of day and the time of year), if there are clouds, if the panel is dirty… but you can’t get more.
What is important is not the temperature, it’s the energy. You can heat up a bottle of water (1.5 L) by 5°C, or heat up a glass of water (15 cL) by 50°C, by using the same amount of energy.
Also, about solar towers : they are more efficient than photovoltaic panels for an equivalent surface. But this is not because the temperature is higher, but because they work differently. The efficiency of the conversion of light into electricity is more efficient with steam turbines than with photovoltaic panels (but turbines are impractical at a small scale).
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