Many people wonder how inefficient is solar energy. However we wanted to take a more positive approach. We wanted to assess how efficient solar energy is compared to some of the other technologies for generating energy. But first some information about the efficiency of solar panels which can be very enlightening.
It turns out that solar panels have a large range. They can range from a theoretical maximum of 55% efficient all the way down to 25% efficient. There are a lot of factors that go into determining how efficient and solar panel installation actually is. We will discuss some of the factors that go into determining some of the real issues.
How inefficient is solar energy
With sunlight shining directly on a solar panel at a 90 degree angle to the surface, the efficiency is going to be a maximum of 55%. This is due to the inherent capabilities of a solar panel. Next the angle that the sun strikes the panel is going to further determine the efficiency. It will change during the day. If the panel is not tracking the sun then the efficiency is going to drop as the sun moves off the 90 degree angle. In addition even with tracking, as the sun sets, there is more air and pollutants for the suns rays to pass through. This drops the efficiency further.
Next it depends on whether you have a sunny day or a cloudy day. On cloudy days or days with snow or rain the efficiency is really going to drop off drastically. Perhaps even below the 25% level on a particularly dark day during the winter. Don’t forget that in the winter in the northern climates there are less hours for the solar panels to generate electricity. Over all the average efficiency can drop to 25% or even lower. It really depends on the time of the year, the time of the day and the type of weather that is being experienced.
Other Types of Electrical Power Generation
It turns out that electrical generation by coal, gas, nuclear or wind plants are also around the 30% to 40% range based on current technologies. The major difference between solar power and some of the others is that all of these power generation techniques are using non-renewable energy sources while solar power is generating power from renewable resources such as sunlight.
Electricity generated by water flowing through turbines is probably the most efficient power generation of all and it is using renewable resources. Efficiencies approaching 90% are possible and far surpass all of the other types of electrical power generation solutions. Some countries are fortunate to have lots of water and lots of potential water power driven generation solutions. They do not need to rely on other fuels and minimizes the use of non renewable resources.
We know that the coal and natural gas solutions are pretty much mature technologies, while solar and wind technologies are just getting started so their efficiency will no doubt improve over time.