How Do Solar Panels Work

Cheryl Said:

How do Solar Panels work?

We Answered:

A solar panel is a device that collects and converts solar energy into electricity or heat. It transfers energy from the sun into electricity or heat which can be used by (for example) nearby buildings. Solar panels can be made so that the sun’s energy excites the atoms in a silicon layer between two protector panels. The atoms split up and the electrons travel down wires into the home for electricity. Solar panels were in use over one hundred years ago for hot water heating in homes. Solar panels can also be made with a specially shaped mirror that concentrates light onto a tube of oil. The oil then heats up, and travels through a vat of water, instantly boiling it. The steam created turns a turbine for power. [1]

Daniel Said:

How do Solar Panels work, and how it can generate electricity?

We Answered:

Solar panels are made up of a number of solar cells. A solar cell will generate from 0.5 to 0.55 volts DC and a current depending on the size and type of cell. The current can be milli-amps or amps. We have a list of solar cell manufactures on our blog under products that are sorted by watts per area. Also go to wikipedia to get more detailed information on solar cells.

Rick Said:

How do solar panels work and how are they installed?

We Answered:

Solar photovoltaic panels contain arrays of solar cells that convert light into electricity. Solar cells, or PV cells, rely on the photovoltaic effect, which describes how certain materials can convert sunlight into electricity to absorb the energy of the sun and cause current to flow between two oppositely charged layers. Individual solar cells provide a relatively small amount of power, but electrical output is significant when connected together as an array making up a panel.

On a bright day, the sun delivers about 1 kW/m² to the Earth’s surface. Typical solar panels have an average efficiency of 12%, with the best commercially available panels at 20%, and recent prototype panels at around 30%. This would result in 200 W/m². However, not all days have bright sunlight, and therefore not enough solar energy can be captured.

solar water heater uses the sun’s energy to heat a fluid, which is used to transfer the heat to a heat storage vessel. In the home, for example, sanitary hot water would be heated and stored in a hot water cylinder. Panels on the roof have an absorber plate to which fluid circulation tubes are attached. The absorber, usually coated with a dark selective coating, assures the conversion of the sun’s radiation into heat, while fluid circulating through the tubes carries the heat away where it can be used or stored. The heated fluid is pumped to a heat exchanger, which is a coil in the storage vessel or an external heat exchanger where it gives off its heat and is then circulated back to the panel to be reheated. This provides an effective way of harnessing the sun’s energy.

Janet Said:

How do you make solar panels work better?

We Answered:

Add some small mirrors around the cell to direct more light on it. If the weight of the mirrors is too much, try foil paper, or using a couple large mirrors held by yourself and classmates, directed at your car.

Billy Said:

How exactly do solar panels work?

We Answered:

There are two types: the ones that heat water and the ones that generate electricity.

The type that heats water are fairly straightforward. Water passes through a tube which is at the focus of a mirror. When the sun shines, the tube gets hot. The water is then pumped to heat a tank of water. In theory, it could be used for central heating – but you tend not to need that when the sun’s shining.

The type that generates electricity uses a number of photovoltaic cells. Each of these works in a similar way to a battery, but uses the principle that a voltage is generated across the junction of two different metals or semiconductors when light shines on them. Each cell produces a small DC voltage but a few hundred of them produce enough electricity to operate some cunning electronics that converts it to something mains appliances can use.

Marshall Said:

How Do solar panels work?

We Answered:

Typical cost is US$ 20k – 50k

Do you want the theoretical physics behind the conversion of light to electron flow? This is a long discussion. See for a good detailed explanation.

Short version is that the sunlight knocks electrons loose from a semiconductor panel, and those loose electrons generate an electrical current.

The solar panels have lots of cells arranged in series parallel to get to a higher voltage (usually 12 or 24 volts) and current. This is sent to charge batteries under the control of a charge controller. The voltage from the batteries is sent to an inverter that converts the 12/24 volts to 120/240 VAC for household usage.


Marie Said:

How do solar panels work? In the easiest way to understand, for those of us who aren’t scientists.?

We Answered:

They’re made of semiconductor materials. If you have no scientific background this is quickly going to get beyond you but I’ll try to simplify.

The solar cells can be made of any semiconductor. Silicon is the most common type because it’s cheap, but there are other materials, even experimentation with organic materials. (By organic here, we mean carbon compounds, not necessarily derived from living things.)

Anyway, the way they work is that there’s what’s called a built-in potential in the material, produced by “doping” the material with small amounts of other materials that change its electrical properties so that current passes easier one way than the other. These junctions are engineered to have a built in potential that’s just a little less than the typical energy of a visible light photon. When the photon hits the material, it pushes an electron from one side to the other. The photon’s energy is thus converted to electrical energy that can power a circuit.

Not all of the energy of the photon turns into useful energy. Some of the photons don’t hit in quite the right spot or the right way to turn into usable energy. They just end up heating the material.

The best solar cells have efficiencies in the 30% range.