ENERGY CONSERVATION AND NEW ENERGY TECHNOLOGIES

Energy plays a pivotal role in the development of a region. Increasing dependency on fossil fuels has caused serious concerns at the local (energy dependency, pollution, etc.) and global (global warming, GHG emission, etc.) levels. Harvesting of energy depends on the availability of resources apart from the economic viability and technical feasibility of meeting the demand. The energy requirement of India is mainly supplied by coal and lignite (19378.24 PJ), followed by crude oil and petroleum products (18432.96 PJ) and electricity (7562.24 PJ).  However, energy consumption in rural India is largely dependent on non-conventional energy sources due to the availability, possibility of rapid extraction, and appropriate technologies. Globalization and consequent opening up of Indian markets has led to urbanization with the enhanced energy demand in the industrial and infrastructure sectors. The perishing stock of fossil fuel coupled with the growing concerns of climate change has necessitated the exploration of cost effective, environment friendly, and sustainable energy alternatives.

1. End-use efficiency improvement: More than 70 per cent of the population resides in rural regions and 85 per cent of the energy requirement is met by traditional fuel through energy inefficient devices. Industrial energy consumption is also inefficient in most of the cases due to the aged equipment, lack of lubrication, torn out parts, and non-scientific combustion. The overuse of energy resources in the commercial domain and unmetered energy supply for irrigation pumps have aggravated the energy crisis.

The primary need of energy resources in rural India is for cooking, water/space heating, and lighting. Most of the energy for cooking and heating is supplied by bioenergy (fuel wood, dung cake, etc.) which is locally available. However, the conventional cook stoves used for combustion of biomass have lower thermal efficiency (<10 per cent). Compared to these, improved cook stoves (ICS) have higher efficiency (20–30 per cent) and there is a scope to reduce 27 to 42 per cent of the fuel wood requirement (Ramachandra et. al, 1999). A typical rural household consumes about 5l of kerosene every month. Average electricity consumption in rural household ranges between 50–60 kWh/month which is mainly used for lighting, entertainment, water pumping, and air cooling. About 30–40 per cent of energy conservation is possible in the domestic sector using CFL/LED lamps for lighting, energy efficient heaters, and coolers (Reddy, 1999).
The domestic energy requirement of an urban household is supplied by electricity, LPG (Liquefied Petroleum Gas), fuelwood, etc. Even though an urban household consumes about 11 kg of LPG per month, 22 per cent of the urban households depend on firewood and kerosene as primary energy need. Electricity is the main source of lighting, cooling, and water heating in urban area where the consumption ranges from 100–125 kWh per month (TEDDY, 2013). Use of ICs, CFL/LED lamps, and energy efficient heaters and coolers can conserve a significant amount of energy. Solar water heater and rooftop solar PV installation can substitute electricity and biomass consumption for lighting and water heating, respectively (Vishwanathan and Ravikumar, 2005).  
Energy conservation in irrigation pump sets is possible by avoiding over capacity installation, maintenance and lubrication, selecting proper foot valves and pipelines, drip irrigation, and sprinkler installation, etc. Energy supply for agricultural purposes is to be metered and tariff has to be applied on the basis of installed capacity. This would help in the optimal irrigation of agriculture fields.  Wind pumps and solar PV pumps can be installed for small area irrigation (5–10 hp) which would replace the diesel or kerosene fueled pumps (Kumar et. al, 2010).
Industries are the highest energy consumers in India which use all forms of energy resources. Many of the Indian industries use coal, oil, and electricity. About 30–40 per cent of energy conservation is possible with upgradation of equipment and technology. However, there is a need to reform policies and tariffs for industrial energy consumption to promote captive generation through renewable energy sources (Gupta and Sengupta, 2012; Ramachandra and Subramanian, 1995).
Energy consumption in the commercial sector has increased considerably during the last decade. Energy conservation in the commercial sector through interventions in lighting technologies (LED/CFL), green buildings, and energy efficient equipment would reduce the energy consumption and decrease the energy intensity.

1. Demand Side Management (DSM): The techniques and measures taken in load side to improve the reliability and quality of power are termed as demand side management (DSM). DSM techniques include use of energy efficient equipment (CFL/LED lamps), reactive power compensators (STATCOM, series/parallel capacitors/inductors), load shifting, and load shaving, etc. (Palensky and Dietrich, 2011). Capacity addition through renewable energy sources is also a DSM technique which reduces the consumer’s dependency on the grid. DSM techniques immediately affect the power system (generation and load) which narrows the supply-demand gap. Demand response, the widely used DSM technique, basically includes two ways—Intensive based programme (IBP) and Price-based programme (PBP). In IBP, consumer will not derive direct benefit for cutting down the load, however, the same shall be earned through incentives such as tax reduction and tax holidays. In PBP, different types of power tariffs are applied to the consumer, from which direct benefit is possible in electricity bills. Various tariffs such as time of use (TOU), maximum demand (MD) pricing, critical peak pricing (CPP), real time pricing (RTP), power factor tariff, etc., will control the electricity bill (Albadi and El-Saadany, 2007).
   
   
2. Smart Grid and Energy Management System: Smart grid is an intelligent system (manual/automated) which integrates all components of the power system (generator, transmission and distribution network, end users) for reliable, efficient, and environment-friendly energy supply. It also plays a key role in demand response, peak load management, unit commitment, and to have effective renewable mix in the installed capacity. Well-established information and communication technology (ICT) and control networks are the backbone of smart grid for which the supportive grid network is required (Vijayapriya and Kothari, 2011). Power sector in India is evolving and adopting modern grid technologies such as supervisory control and data acquisition (SCADA), energy management system (EMS), distribution automation (DA), advanced metering infrastructure (AMI) such as prepaid meters, etc. However, the communication network is limited to high voltage transmission equipment and feeble parts of the present power network need to be strengthened to have the smart grid architecture. India is planning to have a full phase smart grid by 2025, for which required devices such as FACT (flexible AC transmission) controllers and phasor measurements units (PMUs) are being installed. Around 14 pilot projects are being implemented by Indian Government under Restructured Accelerated Power Development and Reforms Programme (R-APDRP) and the US–India Partnership to Advance Clean Energy-Development (PACE-D) programmes. Data management technologies and automatic screening of data, collected through remote terminal units (RTUs) is the worldwide challenge to make the network smart and to take quick decisions (ISGTF, 2013). However, smart grid is a visionary and revolutionary change in the power sector which requires contributions from industry, academic, and research institutions. Smart grid architecture varies from place to place and essentially depends on the present grid structure, load dynamics, and resource availability. The Indian power sector still suffers from huge unmet demand due to lack of peak load management and high T & D losses. Smart grid would primarily reduce the network losses and narrow the energy demand gap. Power sector should be analysed, considering the future demand and then the grid architecture should be decided, whereas replicating the smart grid architecture may not be the solution.
   
   
3. Innovations in Energy Sector: Development of economically viable and technically feasible new energy harvesting technologies is expected to change the present energy mix. Technology innovation in non-fossil energy resources - solar thermal and PV, bioenergy, off-shore wind, hydrogen, artificial photosynthesis, etc. would meet the future energy demand (Abas, Kalair and Khan, 2015). The current focus is on bioenergy, bio-oil, and biological hydrogen production. Technologies like bio-oil and ethanol production from algae would significantly replace the fossil oil for transportation and electricity generation (Gupta and Verma, 2015). Many of these technologies are in the lab scale at the moment and thus, have shown great potential in cutting down the cost and also tapping a wide range of renewable energy sources.

Significant improvements are also found in energy storage technologies in order to resolve the intermittency issues in renewable energy sources. Table 1 summarizes a few energy storage technologies which are being developed and also used across the globe. However, industry collaboration would be necessary in order scale up/widen the new energy technologies and also for wide-scale dissemination.

Table 1: Energy storage technologies (Decourt and Debarre, 2013; Paksoy, 2013)

1. Future Energy Scenario: Natural resource exploitation in the country has increased manifold over the years to cater the energy requirements in all sectors. Resource extraction is forecasted till 2021 using the historical rate of consumption and is given in Figure 17. It shows an increasing trend which necessitates the immediate energy conservation and exploitation of non-conventional sources of energy. Extraction of coal resources is projected as 674 million tonnes, which is about 34 per cent more than the present consumption (2011). Estimation also reveals an increment of 38 per cent and 31 per cent in crude oil and petroleum production consumption. Increase in the natural gas consumption is expected to be marginal (~25 per cent) with respect to the present consumption. This demands radical government policies focusing on renewable energy, revolutionary improvements in end-use technologies, and changes in the resource utilization practices. Nevertheless, the current trend of consumption of fossil fuel resources has caused many environmental problems, thus, necessitating restructuring of energy portfolio. 

Figure 19: Resource consumption prediction for 2021

Renewable sources of energy such as solar and wind are emerging as viable alternatives to meet the growing energy demand of the burgeoning population. Strengthening of transmission and distribution network with the integration of local generating units (RE-based standalone units) would help in meeting the demand. Distributed generation (DG) with micro grids are required to minimize transmission and distribution (T and D) losses, and optimal harvesting of abundant local resources (such as solar, biofuel, etc.). The focus of the current communication are i) understanding the energy scenario in India; ii) sector- and source-wise energy demand with the scope for energy conservation; and iii) prospects of renewable energy with smart grids to meet the distributed energy demand while optimizing harvest of local energy sources.