So you have heard about an electric grid. Almost all of us get our electricity from this grid. But what about mini grids, smart grids or even how batteries of electric vehicles (EVs) can be used for power storage? Let’s decode what each one stands for and look at the way EVs will reshape mini grids once electric mobility enters evet=ry nook and corner of the country.
What is an electric grid?
Electric grids have been the backbone of modern infrastructure for over a century, providing power to millions of people around the world. These centralised complex networks of power plants, transmission lines, and distribution systems essentially carry electricity from the source of power generation and deliver it to millions of people around the world. From powering 20 light bulbs using a steam engine in 1879 to generating 617 exajoules (1018 joules) of energy annually, the electricity generation and transmission network has advanced beyond what once could have been imagined. Given that, the reliability and efficiency of the electric grid can have a significant impact on our daily routines, from powering our devices and appliances to supporting critical infrastructure like hospitals and emergency services.
How does an electric grid work?
Upon generating electricity, the transmission lines need to operate at high voltages ranging from 115 kilovolts (kV) to 765 kV in order to transport electricity over long distances from power plants to distribution substations. Distribution lines, operating at lower voltages ranging from 120 V to 480 V then deliver electricity from substations to homes and businesses. A simple way to understand voltage is to imagine electricity as water and voltage as the force at which it is being pumped through the pipeline.
Are electric grids climate friendly?
As we continue to rely on electricity for more aspects of our lives, ensuring the stability and sustainability of electric grids will become increasingly important. Over two-thirds of the present energy requirements is met by burning fossil fuels, and therefore, electricity, at present accounts for almost 40 percent of the greenhouse gas emissions. An efficient way to do so is by switching over to cleaner sources of energy like wind, solar, nuclear, and hydropower, while systematically discontinuing fossil fuel powered power stations as pledged by countries like Indonesia, South Korea, and Poland.
But renewable energy is variable in nature and thus can’t be controlled like coal-based power plants where more coal would simply result in more power. Since the sun and the wind can’t be controlled, therefore, in order to deal with the storage issues which will arise on switching the grid to renewables, there needs to be installation of more transmission lines and creation of a localised power generation and storage infrastructure.
Apart from that, a centralised grid can get easily disrupted when natural calamities like hurricanes and storms strike a region, resulting in complete blackouts and disruptions in essential services like clean drinking water and medical facilities, until they are restored.
How do mini-grids work?
In many remote or underdeveloped areas, the traditional electric grid model can be challenging to implement, leaving people without reliable access to electricity. This is where mini-grids come in. These decentralised, localised systems are changing the game, providing a sustainable and cost-effective alternative to the traditional grid model.
Mini-grids generate and distribute electricity locally using a combination of renewable energy sources, such as solar, wind, and hydro, and conventional sources like diesel generators. These systems can be customised to meet the specific energy needs of a community, making them more efficient and cost-effective. It typically consists of several components, including power generation sources, energy storage systems, and a distribution network. Energy storage systems, such as batteries, are used to store the excess energy generated by the power sources when demand is low. The stored energy can then be used to meet demand during periods of high energy consumption or when the power sources are not generating electricity. The electricity generated by the power sources is then distributed through a network of power lines and transformers to the customers in the community or area being served by the mini-grid.
Benefits of mini-grids
In socially and economically backward regions of the world, mini-grids can power homes, schools, hospitals, and other essential services, improving the quality of life and enabling economic development of the place.
In some cases, mini-grids can also be connected to the larger electric grid, allowing excess electricity to be sold back to the utility company or to access power from the grid during periods of high demand. Mini-grids also have the potential to improve energy security and resilience, as they are less vulnerable to disruptions caused by natural disasters or grid failures.
Mini-grids and electric vehicles (EVs)
One of the key benefits of mini grids is their potential to support the adoption of EVs in rural areas. EVs have emerged as a viable and sustainable transportation option, as they produce fewer emissions and require less maintenance compared to traditional vehicles. However, in areas without reliable access to electricity, charging EVs can be a challenge. Mini grids can provide a reliable and affordable source of electricity for charging EVs, enabling the use of these vehicles in remote areas.
As per a study conducted by Rocky Mountain Institute (RMI) in India and Nigeria, it was concluded that mini-grid powered two-wheeler and three-wheeler EVs can be financially competitive with conventional vehicles if they are used “as much as possible”, in rural areas. Along with ensuring the recovery of investments in a two-wheeler EV within its lifetime, it will also ensure the financial sustainability of the mini-grids as well.
In addition, mini-grids can be designed to prioritise the charging of EVs during times of low demand, such as at night, when the availability of electricity is typically higher. This can help reduce the strain on the grid during peak hours and ensure that EV owners have access to reliable charging infrastructure. Furthermore, mini grids can support the development of small-scale businesses related to EVs, such as charging station operators and maintenance technicians. These businesses can provide employment opportunities and stimulate economic growth in rural areas.
Can EVs be used to ‘charge’ the micro-grids?
At times when an EV is not being used, it can provide its energy back to the electric grid through the Vehicle-to-Grid (V2G) technology. It works by using bidirectional chargers that are installed in EVs. These chargers allow the vehicle’s battery to be charged from the grid when energy is needed and to discharge energy back into the grid when there is excess capacity.
The benefits of V2G technology are numerous. For one, it allows EV owners to earn money by selling excess energy back to the grid. Additionally, it can help to reduce the load on the electric grid during periods of peak demand, which can help to prevent blackouts and reduce the need for expensive new infrastructure. It also supports the integration of renewable energy sources like solar and wind, which can be unpredictable in terms of energy production, by allowing EVs to store and discharge excess energy when needed. V2G technology has the potential to revolutionise the way we use and think about electric vehicles, by turning them into not only a means of transportation but also a valuable asset in the energy infrastructure.
Mini-grids offer a promising alternative to the traditional electric grid, particularly in rural areas where access to electricity is limited or unreliable. They provide a reliable and cost-effective source of electricity and can support the adoption of sustainable transportation options such as EVs. As the world continues to transition towards a more sustainable and decentralised energy system, mini grids are likely to play an increasingly important role in meeting the energy needs of communities around the world.