Monday, 13 April 2015

What is Vehicle-to-Grid ?

You might have come across this term vehicle to grid if you own an electric vehicle (EV) or not, but if you own one, I definitely recommend you understand this term to make the most out of your EV.

So, to start...

As an aware EV owner, you ought to know that your EV has a battery, which can store energy to power your EV. This battery is also probably the costliest part of your EV. But what you may not realize is that the battery can do a whole lot of things other than just powering your EV, like helping the electricity grid.

Wait wait... what is the electricity grid ? That sounds confusing...

Well... it is not as confusing at it sounds.Let me explain. Electricity is consumed at our houses, though it is generated at power plants, which are situated very far away from our homes. This electricity is delivered to our homes through a network of wires or cables, which make up the electricity grid.

Why does the grid need help from me ?

A peculiar thing about electricity is that storing it is pretty expensive. Therefore electricity is generated at the time of use and consumed immediately. The function of the grid operator to balance supply and demand at all times. So, during the day time, when everybody needs to use energy to power their laptops, phones or to cook or use the washing machines, the demand for electricity is higher and more power plants are needed to be operated to supply that demand.These power plants run on fossil fuels and emit greenhouse gases thereby, dirtying the air and the environment. On the contrary, the demand for energy is low during the night when the majority of the people are sleeping and therefore, most of the power plants can be shut down. Except that this is not possible because these power plants take a lot of time to start and hence, need to stay online to provide us energy whenever we need it. But when the demand is low and the generators are running, it can be hard to dissipate the extra energy.

So what can I do to help the grid and how does V2G come into the picture ?

You can supply a part of the energy stored in your EV battery to the grid during times of high demand (ensuring you have sufficient energy to reach home). This will lend the starting of fossil fuel fired power plants unnecessary. Your individual contribution may be insignificant, but when combined with the efforts of other EV owners, can make a huge difference to the grid and the cleanliness of the environment. This concept of EVs supplying energy back to the grid is called V2G.  Your utility which provides you electricity may even be willing to pay you for the service, since you helped them to supply a part of the electricity, which they would otherwise have bought for a higher price in the energy markets (yes, there is one for buying and selling electricity !)

The next thing you can do is charge your EVs at night. This will make it easier for the grid operator to dissipate the extra energy produced by the power plants that are online. Additionally, if you are on a time-of-use (TOU) rate, it will be cheaper for you to charge EVs during the night, thereby, leading to increased savings.

What is TOU rate ?

Time of use rate is a tariff structure, in which you are billed not only according to the electricity you use, but also according to the time you use it. So, if you use electricity during hours of high demand, you will be charged more than if you use it during the hours of low demand (such as night time). If you are on a flat tariff structure, you are charged the same at all times, the price being the approximately average of the high demand and low demand prices. You should contact your utility to gain detailed knowledge of the tariff structure you are on.

So long story short, V2G means charging your EV at times of low energy demand and providing energy to the grid when it needs it the most and getting paid for the services you provide, so that both you and the grid benefit from your EV.

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