Commonly Used Solar Power Home Applications

Though installed solar electric capacity currently constitutes a negligible percentage of India’s total electricity installation, certain solar power applications have become increasingly popular over the years. Of these, solar cookers, solar water heaters, solar battery chargers, solar lanterns, solar home electricity systems and solar emergency systems have proved to be viable and effective in several parts of the country. In far flung villages, solar photovoltaic panels are used to power applications ranging from a single domestic light to an electricity system for the entire village. In this article, we will take a look at some applications that home users might find useful.

Solar water heating systems based on solar thermal technology have been adapted for domestic use and can heat enough water daily to serve a family of four. This system has the capacity to heat 100 litres of water per day. A solar collector is used to concentrate the sun’s rays. Then, water is heated to around 60 degrees centigrade and stored in an insulated stainless steel tank, which is reported to be capable of storing water at the same temperature for around 48 hours. This system is installed on rooftops. Water flows into the system from the overhead water tank and hot water is piped to faucets in the house. This is an effective way for home users to have access to hot water round the clock without having to rely on conventional electric supply. Vendors claim the system has a 15 year life span and the collectors come with a 10 year guarantee. However, solar water heating systems do not come cheap. Normally, they cost around Rs. 18,000 for a 100 litre system. It is possible, though, to avail of bank loans at relatively low rates of interest to purchase these systems for domestic use.

Another very useful domestic application is the solar cooker, which also uses solar thermal technology. This is a box shaped device, which holds four aluminium containers in which ingredients are placed. The cooker must be kept in the sun with the mirror adjusted to focus maximum sunlight. Cooking time depends on the ingredients, quantity and type of cooking. On an average, the cooker should be left in the sun for around three hours. This gadget can also be used to warm food. The solar cooker is compact enough to carry and is not fuel dependent. These systems generally cost upwards of Rs. 1500.

The solar lantern is an application that is particularly handy in areas that either have erratic power supply or no electricity at all. This is a portable device, which employs a 10W solar panel. The panel is placed in the sun and connected to the lantern by a cable. The solar module converts sunlight into electricity, which in turn charges the battery. On a sunny day, the battery is sufficiently charged to produce roughly four hours of light a day. The light is bright enough to enable a person to read and write in a fairly small room. The reported life spans of the solar panel, battery and bulb are twenty, three and five years respectively. Though this device costs around Rs. 4000, it is fairly affordable because the Government subsidises it to the extent of Rs. 1300 and it does not come with recurring costs and is maintenance free.

A basic solar home lighting system, which uses a 35W solar panel, is very useful during power outages. The panel requires at least two hours of sunlight daily. The system has the capacity to power two CFL lamps and one small fan. The apparatus is subsidised by the Government and requires no maintenance.

Solar battery chargers are also useful devices where conventional electric charge is not possible. Rechargeable batteries used in home and personal use appliances can be charged using solar battery packs.

These applications have proved useful and cost – effective in the residential and small enterprise segments. Solar devices are also eco –friendly and their use helps reduce carbon emissions.