Centre for Research in Alternate Systems of Energy

centre for research in alternate systems of energy

Buildings and Energy

Building activity is a very energy intensive industry; in fact in Europe buildings accounts for as much as 40% of the total amount of energy consumed. In India the overall figure is much lower at 18% but in the larger Metros in India, the energy consumption figures for the building industry would be roughly similar if not more due to transmission losses, illegal connections taken by slum colonies, outdated conversion equipment leading to inefficient use of available power supply and other such factors unique to the Indian context. It is therefore of prime importance that an effort should be made to make them as efficient as possible. The impending energy crisis has made it all the more important that steps be taken in this direction without delay. Research efforts in this field are currently scattered across India, which makes it difficult for professionals to get hold of relevant information. At the same time research efforts have not been converted into practical applications for the market. This has led to the need for an Integrated Research Centre, which would combine R&D with efficient marketing to popularise the use of alternate systems of energy. It would also encourage the use of passive measures to reduce conventional energy consumption in buildings.

Conventional Energy Systems-AN OVERVIEW

Conventional energy systems include coal, crude oil, natural gas, hydroelectric power, etc. that have been used over the years as energy sources. However, these limited reserves cannot last forever. Therefore even if sufficient reserves do exist to take us into the 21st century, it would be selfish of us not to think of the succeeding generations and their energy needs. The world’s reserves of coal are estimated at 1.16X10^6 Mt., 80% of which would be consumed by the year 2025. At the same time proven reserves of oil in the world in 1993 stand at 1000 billion barrels which may last us for 50 years more. The major consumers of fuel are the automobile sector and the building industry; while the auto sector uses oil as fuel, energy consumed by buildings is mainly in the form of electricity. The estimated recoverable reserves of oil in India in 1990 were 758Mt. (India 1991,Research & Reference Division, Ministry of I & B). The present rate of production cannot be sustained for more than 25 years. India has ample resources of natural gas but a large percentage of this is wasted as it gets flared during the refining process. Hydro-electric power has the potential to provide multiple benefits such as power supply, irrigation, water supply to the surrounding villages, etc. The high initial cost is, however a hindrance along with the environmental fallout as also the social concerns for the rehabilitation of the displaced villagers and water sharing disputes between states. The energy situation in India is difficult, to say the least. Every Indian state passes through an energy crisis at some time of the year.

The consumption of power has grown in leaps and bounds and the demand for power is on a steep increase. The rate of domestic production is also on the rise but it is just not enough to keep pace with the growing appetite of the Indian consumer. The demand for energy is growing rapidly and it is estimated that the deficit between demand and supply is going to be about 10% to 15% in the next 10 year period. The present per capita consumption of electricity in India is about 250kWh while it is 10,000 kWh in developed countries such as USA, UK Canada. Even if we have to achieve 500kWh per capita consumption in the next 10 years, we would have to double our installed capacity of power generation. With the present installed capacity at 81,000MW, the present energy resources and finances are not sufficient to sustain an annual addition of 8000MW (i.e. a 10% increase per year). A number of huge so-called `fast-track` power projects are being cleared by the Govt. and river valley projects are also being implemented. The oil supplies of India are the most vulnerable as the domestic production of crude oil is negligible. In addition the environmental impact of the pollutants released in the use of these conventional systems cannot be over estimated.

Alternate Energy Systems -TOWARDS THE FUTURE

The term alternate energy refers to such forms of energy supply, which have not been exploited for large-scale commercial applications. These include nuclear power, wind energy, solar energy, biogas, biomass, tidal energy and geothermal energy. Most of these new forms of energy production are environment friendly and renewable. The main obstacle in the path of popularising these options is their high initial cost and low efficiency. While nuclear power has been successfully exploited around the world; in India the share of nuclear power in the total is just about 2%. At the same time the tremendous cost of installation of the plant as well as the danger of `nuclear meltdown` are making these projects increasingly risky. In addition, India’s stocks of Uranium are very limited, putting a question mark on the long-term feasibility of such projects. Many of the reactors are presently not working to their full capacity due to non-availability of raw material, among other reasons.

Solar and wind energy have received the greatest attention among the other renewable energy sources. Solar energy is abundant all across India and the potential for development of solar-based energy systems is enormous. Research into this field is being encouraged by the Govt. along with other renewable energy systems. The use of wind energy systems is limited to regions where sufficient wind speed is available for the operation of windmills and turbines. To encourage the use of such systems the Govt. of India through State energy development agencies as well as IREDA provide incentives such as soft loans, tax benefits to manufacturers of such systems as well as subsidies for setting up such systems. This has led, in recent years, to a marked increase in the use of these energy systems, for e.g. there has been an increase of 10% per annum in the industrial application of solar hot water systems alone in the past two years.

The greatest application of these systems is in the remote rural areas that are not connected to the grid line. In such villages solar energy can be used for street lighting, water pumping, desalination plants for the supply of clean drinking water, etc. Biogas and Biomass gasifiers are also ideally suited to rural agrarian communities where the farm refuse can be put to use for producing gas which can be used as fuel. Many remote railway stations in Rajasthan, M.P., and other states have been electrified using solar energy.

Over the years the use of clean alternate energy systems such as solar, wind, biogas and biomass are finding acceptance in the residential, industrial, institutional as well as commercial sectors. Sustained research efforts into the field have helped in reducing the cost as well as increasing the efficiency of these systems. But these efforts have suffered from the lack of marketing support. Most of the institutes involved in the field lack facilities and funds to market their products due to which breakthroughs are slow in filtering down to the consumer.

Research efforts in India A BRIEF HISTORY

Research efforts into the field of alternate energy systems have been going on around the world since the `50’s. In India however steps in this direction were taken only in the late `60’s and early `70’s through the Ministry of Non-conventional Energy Sources (MNES). Indian Renewable Energy Development Agency Limited (IREDA) was set up in March 1987 as the nodal agency for co-ordinating the efforts of various state energy development agencies which were set up to encourage research into the field and also to popularise the use of alternate energy systems in the country. The main aims in setting up of IREDA are:

• To promote Renewable sources of energy
• To extend financial support for generation & conservation of energy
• To provide financial support to manufacturers of NRSE systems and devices
• To facilitate leasing of NRSE equipment.

Gujarat Energy Development Agency (GEDA) has been very active in the promotion of alternate energy systems due to which Gujarat has probably the largest installed capacity of such systems. This shows the difference made by efficient marketing and publicity to the spread of these systems. Other state agencies are also involved in such activities, but have been less successful. Other private and govt. aided institutions are also currently involved in such research like Sardar Patel Renewable Energy Research Institute (SPRERI), Anand, Solar Energy Centre, Gurgaon, School of Energy Studies, Pune, Tata Energy Research Institute (TERI), Gurgaon, Centre for Energy Studies, I.I.T., NewDelhi, etc. In addition to research into the utilisation of alternate energy sources, research into Solar Passive Architecture as well as energy conservation in buildings is also being dealt with. But an integrated approach to building design using the principles of solar passive design, energy conservation, and use of active systems is absent. Consultative centres for designers and architects are also very few making it difficult for them to come up with a totally integrated energy saving approach to building design. An effective combination of solar passive architecture, energy conservation and use of active systems would definitely lead to lower energy consumption in our buildings.

an Integrated Research Centre-NEED OF THE HOUR

The condition of the Earth’s atmosphere and ecology has reached a state where further degradation could be disastrous. Environment friendly technology is the need of the hour. Buildings contribute significantly to this pollution of the environment and efforts into the field of ‘greener’ buildings need to be stepped up. Research into this direction has been going on in Europe and the U.S. for a long time and they have gained considerable headway in the subject. Similar research in India on the other hand has been slow and disorganised. In the last century, the United States was able to benefit from oil technology in a way that England, heavily invested in oil based technology could not. Japan, its factories destroyed in the Second World War benefited from the opportunity to build a new industrial infrastructure unhindered by ageing physical plants. A similar opportunity awaits us in the developing world, where the need to rebuild the existing industrial infrastructure will benefit more from investing in new initiatives and technological innovation, than will attempting to replicate obsolete technology developed in the West. Investment in R&D is therefore of prime importance. Environmental awareness is also quite poor among the general public due to which concern for the environment and enthusiasm for greener options are conspicuous by their absence even in the larger Metros. This has hindered efforts to popularise the use of alternate energy systems in India. At the same time research institutes scattered around the country hardly interact with each other and co-ordination of research efforts is missing.

The key issues in popularising climatic design and the use of alternate energy systems are:

• Development of simple qualitative basis for design
• Close integration of alternate energy systems with architectural, cost and functional considerations into building design
• Communication with the user community to increase their level of awareness.

Therefore, a research centre where work is carried on in the field of integrated energy conscious building design would be of national interest, providing assistance to architects and engineers with detailed and complete information in energy saving design. Along with dissemination of energy related information, the institute would carry out advanced research into the high efficiency solar photo-voltaic cells, practical applications for available technology and also endeavour to co-ordinate between research organisations, corporate sector, N.G.O.’s working in the field and the Government.

Solar Energy

Sun, the centre of our solar system delivers 17,000 million MW of energy every year to the Earth, an amount 15,000 to 20,000 greater than is currently utilised on the planet. The Sun, a continuously renewing source of energy is the living source of heat and light for the Earth. Since humankind first created shelter, builders and architects of ancient civilisations have sited and designed their buildings to take advantage of the sun's heat and light, what we now call solar architecture. Solar energy systems contribute to the health and well being of the occupants of the building as well as the surroundings. In addition, they reduce the dependence on conventional energy systems, which are scarce and more importantly damaging to the environment. Like a living organism, the solar building continuously seeks the path of the Sun. The building becomes a skin that orients the occupants to the universal calendar. The object of the building should be to synchronise the beauty and comfort of the natural world with the internal environment.

The solar radiation data available gives the values of energy per unit area at select locations. Accurate information of the available solar radiation at a given place is essential for the design of efficient solar energy systems. One has to ascertain the maximum and minimum levels of radiation at a place and adopt a suitable value for the design of the system.
Considering the radiation available in different parts, India is divided into five zones. The global radiation varies from 3.5 to 6.3 kWh per day per sq.m. more than 80% of the country receives an average solar energy radiation level of above 5.2 kWh per sq.m. on horizontal surface. Thus, there is great scope for the use of solar energy for various applications in our country.

A number of systems utilising solar energy have been developed over the years mainly for the purpose of heating space as well as water, and other associated applications such as solar dryers, water distillation plants as well as photovoltaic cells which converts solar energy into electricity. Solar energy utilisation techniques can be classified as passive, active and hybrid systems.

Biomass Energy

Biomass fuel was the first energy source harnessed by man predominantly in the form of wood. Although wood and other biomass fuels account for only 11% of energy used worldwide, it remains the primary source of energy for more than half the world’s population. Biomass energy involves the conversion of organic feedstocks, such as wood or peat, into useful forms of energy such as heat, electricity or liquid fuels. Biomass energy provides an attractive alternative to fossil fuels, in developing countries, as it readily available and when properly managed the resource is renewable and has little adverse environmental impact. Although practical considerations place limitations on the amount of biomass that can be collected and used if all the energy stored in biomass were made available for human use it could provide about 10 times the total energy requirement world-wide. However, efficient management of biomass is of utmost importance as indiscriminate harnessing of sources without proper compensation can lead to large-scale deforestation and disturb the ecological balance with disastrous consequences.

Biomass energy conversion technologies include combustion, biogas production, waste-to-energy conversion, gasification and pyrolysis, and ethanol fermentation.

Combustion
Energy production from biomass through combustion is the most common technology, but is usually economical only when the raw material is available at little or no cost and is burnt near the source. Transportation costs for unprocessed biomass are far greater than for fossil fuels as they contain less energy per unit volume than fossil fuels. Therefore, before being transported, biomass must first be converted into a fuel with higher energy density. This is done by compressing the material. Wood and its residues, for example, can be converted into dense pellets, cubes or briquettes.

Biogas production
Simple biogas producing devices create anaerobic digestion by decomposing organic matter like crop residues or domestic wastes in an oxygen deprived environment. The resulting biogas-a mix of other gases-can be burnt to provide energy for cooking and space heating, or create electricity to power other equipment. Since many of the parasites and disease producing organisms in the waste are killed by the relatively high temperature in the digester tanks, the digested material can also be used as fertiliser or fish feed.

Waste-to-energy conversion
In waste-to-energy conversion, municipal solid waste (MSW), which is typically collected and disposed off in landfills at considerable cost, is converted to liquid or gaseous fuel. It has several distinct advantages. Unlike other biomass, MSW must be collected regardless of whether it is used for energy production or not. The extraction of biogas from landfills converts potentially explosive methane into energy, also reducing the risk that it will infiltrate surrounding air and buildings. The greatest disadvantage with the system is that a greater initiative is required from the Government for the setting up and functioning of such plants due to the high initial costs associated with the plants.