Solar energy is renowned as a particularly green form of energy. But, is it desirable as an energy source? Here, we help you to understand the meaning, advantages and disadvantages of solar energy so that you can make up your own mind.
What is Solar Energy? – Meaning
‘Solar’ just means ‘from the sun’. And so, solar energy is energy that comes from the sun. Solar energy is a way of harnessing the energy in the sun’s rays and using it for all sorts of things, from generating electricity in our homes to powering the pumps in a swimming pool.
Solar energy refers to:
- electromagnetic radiation energy obtained from the sun (example: visible light, ultraviolet, infrared);
- sun’s energy emitted in the form of waves or rays;
- conversion of sunlight into electricity (example: solar cell or photovoltaic cell);
- making use of light and heat of sun to produce thermal energy (example: solar thermal energy);
- concentrating sizeable area of sunlight into a small compact area to generate heat and electricity (example: concentrated solar power);
- absorption and collection of sun’s heat (example: solar thermal collector);
- using the light and heat of sun for heating water (example: solar water heating);
- artificially producing oxygen (O2) and carbohydrates using sunlight along with carbon-dioxide (COs) and water (H2O) – (example: artificial photosynthesis);
- passively using the sun’s energy (example: drying of washed clothes under sunlight);
The most common form of solar energy is the electricity generated directly from solar cells (also called photovoltaic energy, or ‘pv’ energy for short). This is because special cells or panels known as ‘photovoltaic cells’ are used to trap solar energy and turn it into electricity. You may know these cells by their more common name of ‘solar panels‘.
Solar energy is a renewable type of energy. The sun will not run out as a result of our using its energy, so solar energy is a renewable and sustainable energy source. This means, in short, that human beings will be able to rely on solar energy for as long as the sun and human beings both exist.
What makes solar energy renewable? Renewable energy is energy that comes from a source that is not depleted no matter how much it is used. This is the case with solar energy. The act of humans harnessing solar energy does not deplete the sun’s energy.
Before we jump right in and make judgements about this energy source, though, let us consider the advantages and disadvantages of solar energy in more detail.
Advantages of Solar energy.
Solar energy has several advantages, both in and of itself and as compared to other energy sources. Here are the key advantages:
1. Environmentally friendly. Renewable energy sources also tend to be more environmentally friendly than non renewable sources of energy. This is the case with solar energy. Generating solar energy does not release huge amounts of pollutants (such as CO2) in the way that fossil fuels do when we combust them to release their energy. Further, they do not involve the huge risks of nuclear power. This makes them one of the most environmentally friendly energy sources around.
2. All natural. Harness the power of nature! Sun’s energy such as sunlight, heat, radiation, etc,. are not made or caused by human effort. It is naturally available in abundance.
3. Cost effective. Once installed, solar panels cost very little to run. Since the running cost is low, some countries have used solar energy so effectively that their overall cost per unit of electricity is even lower than the traditional thermal power.
4. Compact. You can add solar panels to your roof without having to install a whole load of bulky equipment.
5. No smells. No smoke or smells are generated from this energy source: just pure, clean energy.
6. Storage. Not everyone knows this, but solar energy can be stored. Using a rechargeable battery is the most simple process of storing solar energy. Modern solar panels are able to store the energy that they generate and that means that even when the sun is not shining, you can still benefit from the energy derived from your solar panels.
7. Perfect for sunny climates. If you live in a country with strong sun, solar energy is perfect for you!
8. Easy to use. Once installed, it is very easy to use solar energy – just turn your appliances, light switches and so on, on and off as you would do normally.
9. Reliable: Solar energy is used throughout the world, and it is widely considered to be a viable and reliable source for the future. Renewable energy sources are good long-term options for the future. Human coal and oil reserves may run out in the next 50 years so we will no longer be able to rely on them. We will, however, be able to rely on solar energy for as long as we need it. The sun has another 4.6-5.5 billion years to live.
10. Suitable for both commercial or domestic use. From small solar chargers that you can use for your mobile phone to large solar panels that can power a whole farm or factory, solar energy is so versatile.
11. Laundry: After the clothes are washed, they use solar energy for drying the clothes. Solar energy can be actively or passively used in the laundry process. Active use includes the use of solar air blowers, whilst the passive way involves placing the clothes directly before the sunlight.
12. Water Heating: Solar water heating devices are placed facing sunlight, and are used in heating water and other fluids. Solar water heating panels are uses both on standalone basis, and in conjunction with traditional electrical heaters.
13: Air Heating using Solar Air Heating panels: Solar air heaters are used in cold countries. Fresh air is drawn from outside and heated by these devices. Thereafter, they blow the heated air in the space that needs heating.
14: Cooking food using Solar cookers: Solar cookers uses direct sunlight to produce heat and cook food like traditional cookers. The important requirements for these cookers to function properly is the availability of enough sunlight and direct exposure to the sun’s rays.
Disadvantages of Solar energy.
For balance, let us now consider the potential disadvantages of using solar panels to generate our energy:
1. Not suitable for winter or cloudy climates. On cloudy days or in the winter, less sunlight is able to reach the solar panels and so your solar panels will not be able to harness so much energy. In these cases, another renewable energy source such as wind energy may be more suitable.
2. Very visible. A solar panel consists of several photovoltaic modules. Some people feel that solar panels look unsightly on their roof. They think that installing solar panels on their roof is not aesthetically pleasing. This can be a particular concern with historic buildings.
3. Installation costs. Some people find the costs of installing solar panels somewhat prohibitive. Though they are cheap to run once they have been set up, solar panels are associated with relatively high installation costs in some cases. This needs to be balanced out b y the money that you will save from using the panel in the long run.
4. Maintenance. Solar panels need to be kept clean so that the sun’s rays can reach them. Some people would rather not have to go to the effort of checking and cleaning the panels every couple of weeks or so.
5. Not suitable for very heavy-duty energy. Most solar generators are perfect for homes, swimming pools and small businesses. They are not always enough to meet the energy needs of larger buildings like factories.
6. Just a fad? Some people see solar energy as just a passing fad. For this reason, they wonder whether they should buy in to this energy source as their main source of energy.
7. Inefficient. Solar panels can sometimes be quite inefficient at generating energy. Solar panels are not 100% efficient. In fact, when photovoltaic cells were first invented, they were able to turn just 1% of the solar energy they received into usable electrical energy. Modern solar panels are usually up to 43% efficient when the sun’s energy is not concentrated so that it is focused on to them. But, when a special apparatus is used to focus the sun’s rays onto the panel, the panel can be up to 85% efficient.
8. Positioning. Solar panels need to be positioned so that they have the best sun exposure – working out the best position for them can take some effort.
9. Other forms of green energy are available. Hydroelectric power or biomass could be better at meeting our energy needs in an environmentally friendly way. For example, if you live on a windy coastal area hydroelectric or wind power may well be a much smart choice than solar power!
10. Regular cleaning is required. Solar panels need to be cleaned on a regular basis so that their surface is always clean and clear and thus able to absorb the sun’s rays to the maximum level. This requires a certain degree of effort.
Solar energy is a green and surprisingly powerful source of energy that is particularly good for people and businesses who live in regions of the world with strong, regular sunshine. Fossil fuels, on the other hand, pollute our planet and they will not last for ever. Thus, finding eco-friendly energy sources is imperative if we want to be able to meet our energy needs and care for our planet at the same time.
Though there are costs involved in installing photo-voltaic cells, once it is up and running a solar energy generator is a very cost efficient way to power your home, pool or small business. A little maintenance is required to keep the panels working properly. So why not look in to getting solar power for your building today?