Tag: production of electricity from solar energy

Box type solar cooker uses a mirror to trap the sunlight inside the box. It needs to adjusted according to the sunlight so that maximum amount of light is trapped inside the box.

Answer is A.

Solar water heating is now a mature technology. Wide spread utilization of solar water heaters can reduce a significant portion of the conventional energy being used for heating water in homes, factories and other commercial and institutional establishments. 
Around 60 deg. 80 deg. C temperature can be attained depending on solar radiation, weather conditions and solar collector system efficiency
Hot water for homes, hostels, hotels, hospitals, restaurants, dairies, industries etc. It can be installed on roof-tops, building terrace and open ground where there is no shading, south orientation of collectors and over-head tank above SWH system.
Hence, the given statement is true.

Solar cell is a device which directly converts solar energy into electric energy.
A solar cell, or photovoltaic cell, is an electrical device that converts the energy of light(sun)  directly into electricity by the photovoltaic effect. It is a form of photoelectric cell, defined as a device whose electrical characteristics, such as current, voltage, or resistance, vary when exposed to light. Solar cells are the building blocks of photovoltaic modules, otherwise known as solar panels.

The statement is true, with upcoming technologies there are solar panels present in watches and these use solar energy to power these watches and for night time there is a small rechargable battery inside the watch,which gets charged enough in day-or during sunlight to power the watch when sunlight is off.

The statement is opposite. Solar cell converts solar energy into electrical energy.

Answer is A.

This is a complex process by which organic matter is decomposed by anaerobic bacteria. The decomposition process produces a gaseous byproduct often called biogas, which consists primarily of methane, carbon dioxide, and hydrogen sulfide. It occurs in nature and can be used to produce biogas from biomass in an anaerobic digestor. 
To optimize the digestion process, the biodigester must be kept at a consistent temperature, as rapid changes will upset bacterial activity. In most areas of the United States, digestion vessels require some level of insulation and/or heating. Some installations circulate the coolant from their biogas-powered engines in or around the digester to keep it warm, while others burn part of the biogas to heat the digester. In a properly designed system, heating generally results in an increase in biogas production during colder periods.
Hence, the statement is true.

The dried manure left after the biogas process is even richer than ordinary muck and makes a fantastic organic fertilizer.
Hence, The spent animal dung left after the production of biogas is an excellent manure.

When solar dryer is placed in sunlight then it convert solar energy into heat energy and heat the air inside the solar dryer to a constant temperature.

 Solar dryer is one of the oldest methods of preserving food for later use.  Foods can  be dried in the sun, in an oven or in a food dehydrator by using the right. So we can dried fruits for longer duration of time.

The basic function of a solar dryer is to heat air to a constant temperature with solar energy hence Solar dryer works on the principle of conversion of solar energy into heat energy.