Solar Energy in INDIA

# Wind Power

Out of the total contribution of renewable sources to the power generating capacity, wind alone accounts for a major chunk of 4434 MW. According to industry sources the figure would have crossed 5200 by March 31, 2006. In fact over the past few years wind energy industry has developed fast, thanks to active participation of the private sector, a package incentives and promotional policies of the MNES and financing through Indian Renewable Energy Development Agency (IREDA). The capacity addition by wind farms has far exceeded the 10th Plan target. Fourth in the world after Germany, USA and Spain in wind power generation, India's potential for wind power has been assessed at 45000 MW assuming 3 per cent land availability. The potential for grid-interactive wind power would be around 15000 MW if sites having wind power density in excess of 300 Watt/sq. m at 50-metre hub-height are considered in keeping with international practice. Wind power turbines and components are manufactured indigenously by a dozen manufacturers and after meeting local needs are even exported. In areas dependent on diesel-based electricity wind-diesel hybrid projects are being taken up. Water pumping windmills are also being promoted.

# Solar Energy

The contribution of solar power at 1748 MW may not be much compared to the vast potential. There are two routes to tap solar energy-one is the thermal and the other is photovoltaic.
The focus of the solar thermal power programme is on research, design, development, standardization and demonstration on all aspects of the current and emerging technologies. A large solar dish has been set up under a research project at Latur in Maharashtra to provide process heat for milk pasteurization. Similarly a number of R&D projects have been taken up to tap solar power for different purposes, including food processing, drying of farm commodities, water heating and cooking. Six lakh solar cookers have been produced. Two thousand concentrating dish cookers and 12 community cookers and 1.5 million sq m of collector area for water heating systems have been achieved. Under the solar photovoltaic programme 55000 street lighting systems, 3.4 lakh home lighting systems and 1566 kW of power plants have been set up. Besides these, 5.4 lakh solar lanterns have been produced. One of the constraints to greater exploitation of solar energy is the low efficiency of photo voltaic cells. Research should be stepped up to increase the efficiency levels of PV cells.

Small hydro sources could yield 15000 MW of power but the achievement so far is only 1748 MW of capacity. As many as 4404 sites with aggregate capacity of 10,477 MW have been identified. Most capacity addition in this sector has been achieved through private sector. India has been a pioneer in Small Hydro Power (SHP) and some of the old and languishing plants are being renovated. Apart from SHP, biomass sources have a big potential estimated at 16000 MW of power. In addition, biomass cogeneration could yield 5000 MW and plantations could yield 77000 MW of which 15000 MW of grid interactive power. However, the achievement has been 491 MW from cogeneration, 377 MW from biomass and 35 MW from municipal waste. The MNES has initiated policy measures to tap the full potential of bio mass and wastes generated in urban areas for increasing the power generation capacity. New and emerging technologies, like hydrogen, fuel cells, bio-fuel, battery-operated vehicles, geothermal and tidal energy, hold promise for meeting the growing energy needs.

# Bio-fuel

The bio-fuel programme has evoked wide interest and the Southern Railways, for instance, have been running two passenger locomotives with 5 per cent blend of bio-fuel. They have planted 75 lakh Jatropha saplings along the railway line. Some States have made available wasteland to Self Help Groups for energy plantations. At the recent South Asia Conference on Renewable Energy President Dr Abdul Kalam observed that the power generation capacity should be increased from present level of 130000 MW to 400000 MW by 2030 to meet the development targets. Of this increase, 50,000 MW should come from hydel projects, 50000 MW from nuclear plants and 55000 MW from large solar energy farms. The balance should come from other non-conventional sources and conventional coal or gas based thermal power plants.

Non- Conventional Energy sources in india

solar rope pump

A close loop of a rope with attached pistons, equally spaced, is pulled through pipe, which is immersed in water at its lower end. The pistons entering the rising main pipe are transporting the water upwards until it reaches the top parts with the spout through which it can escape. Pulling the rope is done by turning the pulley wheel, placed at the top. The friction between the pulley-wheel (made of a cycle rim) and the rope pulls the pistons through the rising main pipe and lifts the water to the spout. The pulley-wheel is operated by a shaft connected to the motor, which is turned in the required direction. A guide near the bottom of the well makes sure that the rope with the pistons is entering the rising main smoothly and pistons are prevented from being hooked at the edge of the lower end of the riser pipe. Rope Pumps are mostly used for drawing water from dug-wells with depths between 0 to 20 m. However, this pump can also be installed on boreholes (0 to 40 m depth), provided an attachment for leading the rope into the borehole and a smaller guide that fits into the borehole casing is available. The simplicity of this low cost pump makes it possible that the users can understand how it works and are therefore able to maintain and repair it.

rope pump guide block

Guide

Tightening the rope for increasing the friction on the pulley wheel can only be done, if the rope with pistons is guided properly, for entering the rising main at the bottom of the well properly. If a tight rope is pulled for a long time exactly around the same turning spot at the well ground, the guiding material needs to be abrasive resistant. Important is also that the whole guiding system for a long rising main pipe is of a certain weight (between 3 to 5 kg), so that the guide is not lifted upwards when the rope is tightened at the pulley wheel. Best results have been achieved with a guiding block cast in concrete.

rope pump

• Raising water from a well with a hand-pump is hard work – and requires a lot of energy.
• To satisfy a family’s domestic water needs, it may be necessary to pump (and carry) 100 litres every day. However this is very little compared with the amount of water required for even quite modest amounts of irrigation.
• It requires a power delivery of about 90 Watts - which is what a fairly healthy human can sustain over time, or what can be delivered by a modestly sized solar panel.
• A vacuum pump of 90 watts capacity can suck water up from atmospheric pressure, in theory this limit is about 20 m. However in practice the maximum depth water can sucked is more like 17-18 m. This means that all the pumps located at ground level are limited to draw water from this depth.
• The rope pump unique means that the weight of the water column inside pumps pipe is spread across all pistons and the water is pushed rather than “sucked”.
• The pump can therefore draw water from an unlimited depth with keeping the bulk mechanism above ground.
• The water pressure remains relatively low throughout.