Vehicle-to-Grid (V2G) technology is not new, but it is still emerging. For many, it is the natural progress from “intelligent charging”, in which electric vehicles are only charged at the best time for the network, to a more holistic network scheme. V2G studies are slow to develop, however, as finding the right business model has proven elusive so far.
An ambitious and exciting experiment is being conducted by Dominion Energy in Virginia. To help integrate a large offshore wind farm, the company incorporated electric school buses as an asset for grid flexibility. When the buses are not expected to be used, the utility company stores unnecessary energy in the batteries and stores it for peak hours.
A new way of sharing energy
Dominion Energy’s experiment, due to be fully functional by the end of this year, aims to share the energy capacity of the batteries in the school buses and create a new way of sharing batteries. The idea is that the buses return to their depots at the end of the school hustle and bustle, where they are connected to so-called bidirectional V2G chargers and thus to a digitally distributed energy management system. This “intelligent” system quickly charges the electric batteries at the optimal time and transfers the rest to the power grid. Although the network called APEX, which is provided by a California-based company called Proterra, is still in its infancy, the goal is to eventually expand it to manage all of the distributed assets including wind and solar technology.
The hope is that the buses’ efforts will reduce the need to add additional capacity to the existing grid and also open the door for greater renewable energy integration. In this example, offshore wind produces clean energy primarily in the afternoon or night when the bus batteries are charging. This should stabilize the distribution network with regard to voltage levels, among other things. Dominion’s experiment targets more than 1,500 buses by 2025, which in theory will provide the storage and overcapacity for more than 15,000 households for much of the day.
Mainstream alternatives and business models
While school buses make an interesting experiment, it is a limited one when it comes to V2G technology. For truly effective scalability, V2G needs to be deployed in a commercial sense for those who run EV fleets, let alone consumers.
A co-funded consumer-facing V2G experiment, conducted by Octopus Energy and known as the Powerloop, is already underway in the south-west of England. The experiment involves paying participants to lease a Nissan Leaf car, which is currently one of only two cars available in the UK with bi-directional charging, and providing them with a free bi-directional charger – the only one of its kind that works from home can.
Participants must charge their Nissan Leaf between 4:00 p.m. and 10:00 p.m. and 5 p.m. so that the energy can meet the peak demand at 6 p.m. Similar projects are carried out by EDF Energy and Ovo Energy. However, the experiments are hampered by the complexity and aging of the UK network infrastructure.
In the long term, the idea is for customers to seek financial incentives by returning energy to the power grid at flexible times. The biggest obstacle at the moment is that the value of the V2G energy is not yet high enough.
To get things moving, a similar approach may need to be used that has already worked for solar rooftops where feed-in tariffs have been introduced by the government, or for utilities that raise the price to make the service profitable. The main obstacle, however, remains the complicated (discrete) structure of the national energy systems and in particular the UK energy system.
Challenges for V2G and the future
Aside from problems with archaic network models, there are no clear regulations for V2G and the infrastructure that enables this is expensive. There is little desire to use bidirectional inverters that can convert direct current to alternating current and vice versa, since unidirectional inverters are most commonly used for fast charging of vehicles. This lack of desire for bidirectional inverters only adds to the cost of V2G.
Unpredictability is also an issue as in order for V2G to work properly, customers need to plug their cars in at the same time. At least for the experiments that are currently being tested, participants need to be closely monitored for when they connect to the network. However, this unpredictability could be avoided when using large commercial fleets, as many vehicles are often used concurrently and not concurrently in such circumstances. They offer ideal opportunities for generating battery energy in order to reduce the pressure on the grids. Interesting proposals to make V2G more attractive to consumers include, for example, offering free parking spaces for connections at airports and shopping centers.
More and more investors are optimistic that V2G will work and see it as an opportunity to reduce the number of upgrades required as more electric vehicles use the grid. It is estimated that the UK could peak around 4.1 million electric vehicles by 2030 and that the energy they could provide could represent up to 16% of the total needs across the country.
The future of V2G technology looks mostly positive, even if the way into the future is not always clear. Other promising news includes the development of a US-based company, Fermata Energy, that has manufactured a bi-directional electric vehicle charger that is the first of its kind to be used at home. And of course the giant Tesla is integrating the V2G functions into the Model 3. Things certainly seem up a gear, but time will tell.
– –Neil Wright is a content writer and researcher for We Buy Any Motorcaravan. He has a particular interest in climate change, the prospect of renewable energies and eco-socialism.