This uses the heat energy of the sun and the main applications for this are:
Solar Water Heaters
Solar water heating or solar hot water is water heated by the use of solar energy. The main components are a collector and an insulated storage tank. The hot water is then piped to the point of use.
Solar Air Heaters
They can heat up houses or chambers. These are designed as per the needs of the particular place and an off the shelf product is not available for this.
Solar Cookers and Dyers
These are available in various shapes and sizes and use different technology starting with the simple box cooker to the concentrated steam systems.
Solar Power Generation Systems
These are gaining popularity in the US, California in particular and here the heat of the sun is concentrated by using mirrors to produce steam which is then used to drive turbines to produce electricity.
Solar Refrigeration and Air Cooling Systems
This is a very exciting area and progress has been made we now have several products in the market like a solar fridge and even air-conditioners which can be purchased off the shelf.