As a RE player iam totally fascinated by the potentiality offered by micro grid as this form of energy generation can function independently from the traditional regional power grid. Furthermore it can with ease fully enable towns, small cities or corporations to develop their own energy sources and power storage systems & distribute or even sell excess power back to local utilities. They also offer a very prompt response during high energy demand times and power outages. Micro grids therefore enable a greater level of penetration for renewable energy with higher efficiency, providing energy savings and carbon footprint reduction. They are here to stay.
While still immature in many countries, there are numerous pilot projects that are paving the way for microgrids. New technology is blossoming in this category. New ground is being broken as utilities and communities work together to protect one of their most precious resources: electricity. In order for the technology to receive its due share, utilities will need to embrace the concept of the micro grid, and how it can both enable and inhibit the business of energy. With knowledge and resources, micro grids can be a vital part of the new and upcoming Smart Grid biosphere.
Micro grids are not actually a new or a novel concept . Many sites have traditionally used embedded backup generators for reliability purposes. However the latest technology backed advanced micro grid Ensures a permanent, clean, local generation, the ability to seamlessly connect and disconnect from the main grid, and the use of analytics to run the system at an optimal efficiency level. Micro grids can also be off-grid systems. They can even go beyond electricity and incorporate gas, heat, and district cooling. They generate and distribute electricity on n a localized basis. Micro grids are comprised of a series of subsystems including their own rooftop photovoltaic generation, wind turbines, generator sets, CHP, energy storage systems and Power distribution systems. Some people tend to think that micro grids are only small-scale grids. Others think any kind of local energy network can be termed a micro grid.
Individual buildings and residential consumers can be considered ‘Nano grids’ if they: a) consume and supply power b) self-consume their own generated electricity and c) isolate themselves from the grid. These smaller micro grid designs can serve residential or commercial loads. They may be configured to provide power to a larger commercial property such as a shopping mall, college campus, or military installation, or even an entire neighborhood. These small grids can be linked together or embedded into larger microgrid.
Micro grids can be categorized into four categories:
Grid-connected facility: With a single owner and connected to the main grid, these microgrids are created for improved reliability in places where the main grid’s reliability is poor, or when the utility is providing attractive pricing incentives for sheddable loads. Some examples are high-availability single buildings, or research or headquarter campuses of a corporation, hospital , Data Centre, etc.
Grid-connected community: Serving multiple consumers and producers, connected to the main grid, or managed as a unit and with an optimization of exchanges with the utility’s main grid, these micro grids range from business campuses of cities and green villages to eco-districts or even small municipalities
Off-grid facility-led: This is the most common type of micro grid today. With a single owner, these are found in remote areas not reached by traditional grid. Examples are military bases, remote mines, isolated mountain homes.
Off-grid community-led: Serving multiple consumers and producers, these micro grids are also found where the main grid is out of reach, for example islands, remote villages, and communities. However, unlike facility-led micro grids that serve one corporation/institution, these initiatives encompass various community assets and aim to guarantee resilient power for vital community services.
So why am I sold on Micro grids ? …well because it delivers power at close proximity to its generation point, thereby avoids much of the overhead costs associated with transmitting and distributing energy, including losses inherent in long-distance energy transport. Secondly, because of its key attribute of seamlessly disconnecting and reconnecting to the main grid without supply interruption of loads. Finally, Micro grids powered by wind, solar, or biomass contribute to the overall renewable goal of the green utility and our society, helping reduce energy-related greenhouse gas emissions.
Powering Rural India through Micro Grid:
Rising demand for energy has given rise to two main challenges for the power sector , the addition of new generation capacity and expansion of the current transmission and distribution infrastructure. Decentralized generation has the potential to solve both these issues, particularly in remote rural areas. Access to modern and reliable source of energy is a major driver for rural development and improved livelihoods in India.
One such sustainable strategy is to create clusters of areas around the rural areas where local renewable energy can be utilized to meet energy demand. The major renewable energy source for decentralized generation within rural areas is likely to be small scale solar home system. As a result the integration of such systems in a low voltage DC network will be a noteworthy step towards powering these societies as an efficient approach. Efficiency, protection, power quality and the relative advantages of DC network. The use of low voltage DC distribution network for rural electrification is an intelligent grid concept to provide local communities in far flung rural villages with electricity supply generated from renewable energy sources. Since these communities subsist with no grid connectivity, they require a concept of micro-grid whereby individual Solar Home Systems (SHS) can be connected. The excess power required by any SHS is supplied from the grid to make the system more reliable. Furthermore, people who cannot afford Solar Home System can connect themselves with the grid as well and get access to the basic need of electricity through a simple power flow supervision system based on domestic and grid level DC electrical systems thereby moving into the self-reliant renewable energy based electricity generation. I feel many of the rural village clusters in India have a lot of potential for new business development based on this micro-grid concept.
Traditionally the Grid Extension and Decentralized Distributed Generation have been the two basic means used to electrify rural areas. Grid Extension GE involves laying out distribution infrastructure to reach out to the villages while Decentralized Distributed Generation comprises small, modular, decentralized off-grid energy systems located in or near the place where energy is used. While grid extension is a costly solution for connecting to remote locations and populations spread over a larger area, it does offer the benefits of being connected to the grid with access to relatively cheaper source of electricity, continuous supply, and access to energy generated by generating stations located far away from the consumption point.
On the other hand, the maintenance of a large distribution network and high Transmission and Distribution (T&D) losses on such a network are issues that the utilities have to deal with. Grid extension becomes prohibitively expensive in the cases of remote villages which are hard to reach due to their location constraints. Most rural electrification in India is currently implemented through this option. Micro grid therefore is the best option for rural electrification that has been implemented successfully across the world in nations such as Cambodia, Nepal, Kenya, China, and Philippines. Micro grid enables electricity generation at the local level using locally available resources ensuring reduced dependence on external resources. Local distribution net-works or micro-grids are set up over a cluster of villages and powered by a local generating plant which may be based on conventional fuels such as diesel, natural gas, fuel oil or on renewable energy such as wind energy, solar energy, hydro power, and biomass.
Penetration of Micro grid into villages: As on 30 April 2010, 16.1 per cent of India’s villages were still unelectrified. These villages are expected to be electrified through a mix of Grid Extension and Micro Grids . MNRE has undertaken the remote village electrification program .Targeting at unelectrified remote census villages and remote unelectrified hamlets of electrified census villages where grid connectivity is either not feasible or not cost-effective. A total of 9259 remote villages/hamlets were identified for rolling out the project, out of which 8332 villages have already been covered.
Installations by Energy Service Companies (ESCOs) of 10,000 renewable micro grids & mini-grids:
India is also planning to spur development of 10,000 renewable micro grids and mini-grids and bring electricity to 257 million people living in energy poverty. Ministry of New and Renewable Energy, the draft plan 2016 calls for 500 MW of installations by energy service companies (ESCOs). The ministry defines micro grids as renewable-based distributed generation, under 10 kW, which can operate on a stand-alone basis or connected to the central grid. Mini-grids are the same except larger, over 10 kW. Funding for the installations would come from the federal government, states and commercial sources.
To encourage ESCOs into the market, the ministry plans to set up a special category of private developer/operator known as Rural Energy Service Providers. The RESPs would receive special incentives and privileges, including upfront capital from the ministry and streamlined approvals. Project developers would become RESPs under a phased process. Before they receive the designation, they can install 10 projects (up to 200 kW) with ministry incentives. The government will then evaluate the performance of the micro grids and mini-grids for two years. If they are deemed successful, the developer earns the RESP title and can install more micro grids and mini-grids.
The national Policy on RE based Mini/Micro grids June, 2016 encourages deploying of decentralized RE solutions to address the access challenge in rural areas in many parts of the country. With reducing costs and increasing efficiencies of RE technologies, RE based Micro and Mini grids solutions are being perceived as a durable solution able to provide reliable and cost-effective energy service, cater to productive and commercial loads, accommodate future loads, and connect with grid and feed surplus power if needed. Many supporting measures are employed by the Government to encourage ESCOs and investors in to the micro and mini grid space.
The Ministry is keen on working with States (and State Nodal Agencies) to build a supportive ecosystem for development an environment able to minimize the risk associated with such investments, and mobilize capital. As micro and mini grids are main streamed, it will enable in meeting the goals of reducing dependency on fossil fuels, providing clean power to rural households, and meeting their aspirational needs.
Village Energy Committee:
The existing legislative and policy framework makes each level of governance responsible for electrification, including the Central & State Government, District Committees and Village Panchayats . As Panchayati institutions play a crucial role to facilitate electrification in villages, there is a proposal for Panchayats to play more active role and should involve the community in the process of growth by constituting a Village Energy Committee (VEC) to ensure participation and commitment of the village community.
The Village Energy Committee (VEC) will work with ESCO to develop and maintain the following project responsibilities:
- Developing a plan and identifying households interested in getting a connection
- Ensuring connections for households on a priority basis & quality of power supply
- Facilitating regular payment of tariffs
- Protection of the equipment
- Curbing the theft of power
- Facilitating resolution of dispute or grievance(s), if any, and others
RE based micro and mini grids with its enormous potential are a promising solution to the access to energy challenge in the country. In my opinion they are best thing to have happen as they offer the benefits of boosting local economy by meeting energy needs of residential and commercial activities thereby supporting enterprise development, generating employment opportunities, raising individual as well as household incomes both in the rural villages and in far flung areas in India.
I like to sign off with PM’s recent quote on the ramparts of Delhi’s Red Fort on India’s 71st Independence Day “ India’s stature in the world is rising. We have to change this ‘Chalta Hai’ (anything goes) attitude. We have to think of ‘Badal Sakta Hai’ (things can change). This attitude will help us as a nation”.
This article is authored by Sanjith S Shetty- Vice Chairman & Managing Director, SOHAM RENEWABLE ENERGY INDIA (P) LTD.