Currently, there are two types of solar power generation. These are: Solar thermal energy and Photovoltaic cells. The latter can be considered as one of the most important and cost-effective technologies available in the market.
Photovoltaic cells
Using photovoltaic cells for solar power generation can be an effective way to convert sunlight to electricity. The amount of electricity generated depends on the cell’s efficiency, as well as the material and location of the installation. A typical residential panel of 60 cells produces 220 to 400 watts of power.
Photovoltaic cells are made of a semiconductor material, usually silicon. The material is specially treated to interact with photons in sunlight. This interaction causes electrons to migrate to the front surface of the cell.
The amount of electricity generated by PV cells varies by semiconductor material and efficiency. For instance, a PV cell made of amorphous silicon can produce electricity at more than 8% efficiency, while a PV cell made of polycrystalline silicon can produce electricity at more than 26.6% efficiency.
Photovoltaic cells are also made of a variety of materials, including cadmium telluride (CdTe), copper indium gallium selenide (CIGS), gallium arsenide (GaAs), and amorphous silicon. Thin film PV cells are fast growing in the commercial solar market.
Solar thermal energy
Various methods can be used to concentrate the sun’s thermal energy for power generation. One of the most effective is called concentrated solar power (CSP). A power tower acts as the central receiver for solar energy. The tower has thousands of tracking mirrors that focus the sun’s thermal energy. The mirrors reflect sunlight onto a receiver where it heats a high temperature fluid. This fluid is then used to create steam to turn a turbine, generating electricity.
Another method is called photovoltaic, which uses lenses or mirrors to focus the sunlight. This produces higher temperatures than the other two methods. Photovoltaic systems are ideal for wide-ranging climates. They can also utilise all the sunlight.
The solar thermal industry is expected to supply 75 per cent of global heat demand by 2050. As such, the industry has a large role to play in reducing carbon emissions. By the middle of the century, it is estimated that solar thermal technology will produce net zero carbon emissions.
Distributed solar power generation
Increasing demand for clean energy, rising energy awareness, and decreasing prices of solar PV modules are some of the key factors driving the global distributed solar power generation market. Furthermore, increasing investments in renewable energy projects and decreasing cost of solar panels are expected to propel market growth.
Asia-Pacific is expected to dominate the distributed solar power generation market in the coming years. Countries in the region, such as India, Japan, and China, are expected to contribute to the market’s growth. However, the United States is expected to witness significant growth during the forecast period.
Several emerging markets are in the process of tapping into these markets. These markets have elaborate plans for distributed solar.
However, the distributed solar power generation market is highly fragmented. The major players include First Solar Inc., Solarcity Corporation, Wuxi Suntech Power Co. Ltd., Canadian Solar Inc., and Juwi Solar Inc.
A key component of distributed solar is the rooftop expansion of industrial and commercial buildings. Currently, only 20% of the world’s distributed solar capacity is attributed to these sectors. This is mainly due to the limited rooftop space of these buildings. However, county governments will be responsible for only ten thousand square meters of the rooftop space. Increasing energy awareness and a growing need for energy conservation are expected to drive market growth.
Feed-in tariffs
Several countries in Europe and Japan have successfully implemented feed-in tariffs to encourage renewable energy development. A feed-in tariff is a contract which guarantees the purchase of energy at a predetermined price above the cost of grid electricity.
The price per kWh depends on the technology used, the size of the solar system, and the location. Some technologies are more cost-effective than others. The cost of installation and maintenance are also factors in determining the profit from a solar system.
A solar system can be cheaper than building new distribution lines. However, the economics of a solar system may not be impacted by a feed-in tariff. A feed-in tariff will help meet state renewable portfolio standards and is a means to encourage the use of renewable energy.
The cost of a solar system will be affected by the type of equipment and the cost of installation and maintenance. Feed-in tariffs are usually paid on a long-term contract basis. However, utilities may change the tariffs to meet their goals.