Tehri Dam is the biggest hydro-electric power project in India.

Waste formed as a byproduct of nuclear reactions is a nuclear waste. Nuclear wastes are highly radioactive in nature.

Coal can be consumed in various form by converting it for electricity generation, liquid fuel, for cement manufacturing, steel production and synthetic fuel etc.

The yield of nuclear energy is enormous and hence it has extraordinary potential as an energy source. It is one of the most low-carbon energy sources.

Various types of pollution are air pollution, water pollution, noise pollution, soil pollution, etc. Space pollution is not a type of pollution.

The solar constant is estimated to be approximately 1.4 kJ per second per square metre.

As our demand for energy increases, we need to look for more and more sources of energy. We could develop the technology to use the available or known sources of energy more efficiently and also look to new sources of energy.

In ancient times, wood was the most common source of heat energy.

The solar cooker cannot be used at night and during cloudy weather. It takes more time to cook food. The direction of the solar cooker is to be changed continuously towards the direction of the Sun.

Slurry left behind is removed periodically and used as excellent manure.

Other than dry cells, i.e., the battery cells, all three devices have been invented to generate, store or directly utilize solar energy. whereas, Dry cells generate energy from a chemical reaction. 

The waste and dead parts of living beings is called biomass. Wastes and dead parts of living being buried deep inside the earth turns up into fossil fuels after a long time.

Nuclear fusion reaction takes place in the core of the sun in which 2 molecules of hydrogen combine to form helium molecule.

Biomass is biological material derived from living, or recently living organisms. In the context of biomass for energy this is often used to mean plant based material, but biomass can equally apply to both animal and vegetable derived material.
Hence, the non-usable animal or vegetable products are collectively called Biomass.

Coal and petroleum are commonly called fossil fuels because they are formed from the prehistoric remains of dead plants and animals buried deep under the earth's crust under special conditions.

The wind energy map gives information about the trend of wind energy of various locations so that we can make wind farms on the sites which receive higher wind energy compared to other places.

Potential energy is stored energy or the energy of position. The potential energy stored in a body of water held at a given height is converted to kinetic energy (movement energy) which is used to turn a turbine and create electricity.
Hence, water stored in the reservoirs of hydro-electric dams has potential energy.

Major problem in harnessing nuclear energy is ,how to dispose its residue which is highly radioactive in nature. It requires proper waste disposal mechanism.

A Thermal power plant is a power plant where steam produced by the burning of fossil fuels is used to drive a steam turbine. This turbine is connected to an electrical generator.

The sun is the ultimate source of almost all kinds of energy on earth, either directly or indirectly.

Biogas typically refers to a mixture of gases produced by the breakdown of organic matter in the absence of oxygen.
Hence, its main constituent will be methane.

Geothermal energy is the heat from the Earth. It's clean and sustainable. Resources of geothermal energy range from the shallow ground to hot water and hot rock found a few miles beneath the Earth's surface, and down even deeper to the extremely high temperatures of molten rock called magma.

The most common way of capturing the energy from geothermal sources is to tap into naturally occurring 'hydrothermal convection' systems, where cooler water seeps into Earth's crust, is heated up, and then rises to the surface. Once this heated water is forced to the surface, it is a relatively simple matter to capture that steam and use it to drive electric generators. Geothermal power plants drill their own holes into the rock to more effectively capture the steam.
Hence, the 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.

In the box type solar cooker, the light coming  from the sun is used to cook the food by concentrating light onto the food material.Hence light energy is being used here to cook food.

Bio-degradable material is kept for a long time inside a closed chamber in absence of oxygen, most of the organic matter is broken down into biogas which is a mixture of methane and carbon dioxide in approximately three weeks. The biogas is collected in a spherical gas holder from the top of the biogas reactors. The gas produced by biomass is knows as biogas.

Wind, water, tides all can be used again and again. But, once natural gas is burnt, it can never be used again.It is in limited amounts on earth.

Tidal energy of sea waves is harnessed by constructing hydro electric dams at the mouth of narrow bays along the sea coast.
Hence, The tidal power plants are constructed near the mouth of narrow bays.

The resources which are exhausted after continuous utilization are known as non-renewable resources. Fossil fuels are non-renewable sources of energy. Coal is a fossil fuel formed over millions of years by the decay of land vegetation.