Solar power is the conversion of sunlight into electricity, either directly using photovoltaics (PV), or indirectly using concentrated solar power (CSP). CSP systems use lenses or mirrors and tracking systems to focus a large area of sunlight into a small beam. PV converts light into electric current using the photoelectric effect.
What is Solar Energy?
The most precise Solar Energy definition is simply:
Energy from the sun.
But what is Solar energy really? There are two types of solar energy:
(1) Thermal Energy
(2) Electric Energy
Thermal Energy
Thermal Energy is everywhere. It’s lights up our days. It heats the earth, our bodies and our homes. It dries our clothes and gives us produce like sun-dried tomatoes. All for free!
It’s also used to heat water for domestic use or even pools. There are two ways in which water can be heated:
1. Actively, when a conventional heating element within the solar hot water system heats water on hot days.
2. Passively, when water is preheated before it is delivered to the cold inlet of a conventional gas/ electric water heater.
Electric Energy
Electric Energy uses the power of the sun to produce electricity through solar cells, otherwise known as photovoltaic (PV). It can be applied in three ways:
1. Stand-alone
2. Grid-connected
3.Back-up
Stand-alone: also called Solar Home System (SHS):
A system not connected to the grid. More often than not, these systems are installed in remote areas where there is no utility-supplied power, like remote holiday cottages.
It is often cheaper to install a solar energy system than lay electricity cables to the site. Excess energy can be stored in a battery for use during times where there is no sunshine.
Grid-connected:
A system where utility supplied electricity is connected to the property, but the owners wish to harvest clean, free energy from the sun. Usually in a quest to live a more sustainable, environmentally friendly existence.
Electricity is supplied firstly from the solar energy system, then the connected battery if one has been installed and finally from the grid if there is still a need. .
Back-up:
A system connected to an unreliable grid or one of poor quality. These types are usually installed in areas where a lot of power blackouts occur. A small system will service the most important electrical appliances and lights, but a bigger system will be required to keep the fridge running during a blackout. LETS LOOK AT A FEW CONSIDERATIONS
TO BUILD SOLAR ENERGY SYSTEMS FIRST.
1 Determine whether you want to install a solar hot water system or one to generate electricity, or both.
2 What is your geographic orientation? Solar panels should be orientated to receive the maximum amount of daily and seasonal sunlight. In the Northern hemisphere solar panels should be facing due south. In the southern hemisphere - due north. A variance of 45° won’t make much of an impact on performance though.
3 Your roof orientation. Has your house got a roof facing the sun most of the day?
4 Look at your and your neighbor’s landscaping and surrounding buildings that might shade the panels.
5 What is the weather conditions in your area? The more sunny the better, but solar panels perform very well in cloudy conditions too.
6 What is the tilt of your roof? The optimal angle is equal to your latitude, although most panels are fixed to whatever angle the roof is tilting without impacting performance.
7 What amount of electricity do you need to power your load? The easiest way to determine your household’s use is to look at your electricity bills. It’s best to use an average of a full year.
8 Whether or not you decided to build solar energy systems, great savings can be had by just installing energy efficient appliances and implementing other energy saving measures.
9 Keep in mind that additional balance-of-system equipment will be required to transfer the generated electricity to the appliances in your house.
10 Always use a qualified professional to connect the electric components.
Homemade Solar Panels;-
This is the fabrication technique that has evolved out of my trials and errors. I'm sure there are many different ways to build solar panels that would work just fine. I have tried to keep mine as simple as possible.
This shows the cells upside down in a jig made from strips of mat board stapled onto a piece of 1/4 inch plywood. At this point, the tabs can be soldered to the cells. I found a 30 watt iron to be the minimum acceptable and a low temperature solder to be the best.
Here the cells are all soldered and a dab of silicone caulk is placed on each one.
Nessun commento:
Posta un commento