Can renewable energy power the world?
Can renewable energy power the world?

This free course is available to start right now. Review the full course description and key learning outcomes and create an account and enrol if you want a free statement of participation.

Free course

Can renewable energy power the world?

3.2.1 Crystalline silicon PV

The most efficient silicon solar cells are made from extremely pure monocrystalline silicon – that is, silicon with a single, continuous crystal lattice structure with virtually no defects or impurities.

Monocrystalline silicon is usually grown from a small seed crystal that is slowly pulled out of a molten mass of polycrystalline silicon, in the sophisticated 'Czochralksi' process developed originally for the electronics industry. You can see the overall process of monocrystalline PV cell and module production in Figure 3.

Polycrystalline silicon essentially consists of small grains of monocrystalline silicon. Solar cell wafers can be made directly from polycrystalline silicon in various ways, which include the controlled casting of molten polycrystalline silicon into cube-shaped ingots, which are then cut into thin, square wafers and fabricated into complete cells in the same way as monocrystalline cells. Polycrystalline PV cells are easier and cheaper to manufacture than their monocrystalline counterparts, but are less efficient.

Figure 3 The overall process of monocrystalline silicon solar cell and module production.

Commercially available polycrystalline PV modules (sometimes called 'multicrystalline' or 'semicrystalline'), typically attain energy conversion efficiencies of around 14%, whereas monocrystalline module efficiencies can exceed 17%.

Activity 1

How much voltage does a typical silicon PV cell produce?

Answer

A typical silicon PV cell produces around 0.5 volts. These cells are usually combined into PV modules incorporating 60–72 PV cells connected in a series- parallel combination. They are normally around 1.4 to 1.7 m2 in area (though some are larger), and have a peak power output of some 120–300 watts, depending on the design and technology.

Now you'll find out about another photovoltaic material.

RENC_1

Take your learning further

Making the decision to study can be a big step, which is why you'll want a trusted University. The Open University has over 40 years’ experience delivering flexible learning and 170,000 students are studying with us right now. Take a look at all Open University courses.

If you are new to university level study, find out more about the types of qualifications we offer, including our entry level Access courses and Certificates.

Not ready for University study then browse over 900 free courses on OpenLearn and sign up to our newsletter to hear about new free courses as they are released.

Every year, thousands of students decide to study with The Open University. With over 120 qualifications, we’ve got the right course for you.

Request an Open University prospectus