Last week, in my roundup of renewable energy sources, I promised to give each source a closer look in future posts. Let’s start off with the Sun and its abundance of solar energy.
As noted in my previous roundup, the Sun radiates almost inconceivable amounts of energy in our direction. If we could utilize even just a small percentage of this solar energy, we could leave all our lights on, never turn any appliance off and generally just splurge on electricity non stop – and still have vast amounts of energy left over.
Realistically, of course, we can’t really utilize every last bit of solar energy. Space requirements and other limitations restrict how much is practically available to us. One thing is for sure, though: there’s certainly enough potential to make solar energy one of the biggest contributors to world energy production.
The Sun is the source of (almost) everything
The focus of this post is on the direct utilization of solar energy. It’s worth noting that the Sun is lurking around in the background of many other renewable energy sources, indirectly driving them:
- Through the water cycle, the Sun drives the processes that make hydroelectricity possible.
- The Sun’s heating of air causes pressure changes in the Earth’s atmosphere. These pressure changes cause air to rush from high pressure areas to low pressure areas, resulting in the wind that makes wind power possible.
- The wind created by the Sun’s heat blows across ocean surfaces, creating the waves that make wave power possible.
- The plants and organic material used for biomass can’t grow without sunlight. Consequently, the Sun is an indirect source of the energy we get from biofuels and biomass.
Using solar energy
Roughly speaking, solar energy can be utilized in two ways:
- The Sun’s heat can heat something
- The Sun’s light can cause an electric reaction
Each of these two main ways come in more than one shape or form.
Solar heating
The most obvious way to take advantage of the Sun’s heat is by directly heating a space, object or liquid. A few examples:
- Heating a room by letting the Sun shine through a window
- Cooking with a solar oven
- Heating the water in a swimming pool
The heat of the Sun is also useful in more indirect ways:
- Heating a liquid in a solar collector used for heating water
- Superheating water into pressurized steam, and then using the steam for generating electricity
- Vaporizing and condensing water in a solar still, to purify and desalinate it
- Powering an engine through heat differences, for example a Stirling engine
Electric reactions to sunlight
While perhaps sounding a bit complicated, most of you will be familiar with at least the first one of these:
- Generating electricity through the use of photovoltaic cells – this is what most people think of as solar cells
- Generating electricity through the use of photochemical cells – currently an experimental technology
Water is next
That’s the end of this summary of solar energy uses. Since it is precisely that – a summary – it merely skims the surface of the existing possibilities. Future posts will look closer at the various technologies and products that are available.
If you think I’ve missed something, or want to comment anything else, let me know in the comments section below.
Next week, I’ll have a similar look at how the energy in flowing or falling water might be put to use. Stay tuned!
This post was tagged with: energy production, renewable energy, solar energy, solar heating, solar power, sun