Alternatives to V2G

From what we have learned so far, V2G is a promising technology with a lot of applications. But it is not the only technology tackling these challenges. In this step we will consider some of the other technologies currently competing with V2G.

There are three main competing solutions for V2G:

• Stationary Battery Storage – Quite literally a fixed battery. These are costly, but effective. They also have a limit to the length of backup they can provide.
• Backup Generators – Powered by diesel, oil or gas. These are well proven technologies, but expensive to run and need regular maintenance. They can run indefinitely as long as you can access regular fuel deliveries. They are however, a relatively dirty and inefficient way of generating electricity.
• Smart Charging – This is standard uni-directional charging, but where you can control the charging rate and time.

How competitive each of these technologies is depends on the application. We will start by considering each of the value propositions explored earlier this week.

Revenue-Generating Energy Trading

Energy trading was historically reserved for businesses with large, flexible power stations or a dedicated energy trading team. However, the barriers to entry for energy trading have been falling from both a regulatory and a technology perspective. With the shift towards renewable energy, flexibility from electricity generation is not so easy to achieve, whilst the demand for flexibility has been increasing. The leading technology emerging to fill the gap is stationary battery storage. Stationary batteries are easier to aggregate and are always available. But there is a significant up-front investment cost which can make V2G appear an attractive alternative.

Smart charging can capture some of the revenue generation available from V2G. Smart charging has a lower capital cost and fewer technical limitations. Work carried out by Cenex as part of the Sciurus project in the UK showed that smart charging was generally able to capture about 40% of the value from this service compared to V2G.

Resilience

Technologies providing this service are commonly known as Uninterruptible Power Supply (UPS) systems. These are usually powered by either diesel generators or a stationary battery. UPS systems provide power instantaneously during a power failure. For most customers this is more important than the size or weight of the stationary system. For this reason, cheaper lead-acid batteries are often used. But the falling prices of lithium-ion batteries and the emergence of a second-life battery market means that the industry is gradually shifting.

V2G is likely to provide a lower cost solution than either diesel or stationary battery UPS systems. Yet it cannot guarantee availability in the same way as a fixed solution as the vehicle could be in use elsewhere when a power interruption occurs. This limits the suitability of V2G to applications where the power supply is only required when the vehicle is likely to be parked. A good example would be a domestic property where the resident needs constant power to a medical device while they are at home.

Achieving Personal Net Zero

Stationary batteries are the main competing solution for optimising on-site renewable generation against local demand. Stationary batteries are guaranteed to be available when needed, but they are an expensive investment. Smart charging also has the potential to provide a limited version of this service. Based on work carried out by Cenex as part of the ‘Understanding the True Value of V2G’ report, smart charging was able to capture between 40-90% of the value from behind-the-meter optimisation compared to V2G.

Benefit to Society

Energy storage systems, including stationary battery systems, as well as other systems such as pumped hydro and compressed air, are again the main competing solution for this value proposition. On a national level, large scale grid-connected stationary energy storage systems aid the deployment of renewables. This can be either directly as part of an energy supplier’s portfolio or indirectly by providing grid services.

Enhanced Battery Management

It is already common for EVs to include simple functionality for managing battery health. This includes pre-set battery constraints, as well as user programmable maximum state of charge limits or charging timers. It is also likely that these systems will become more sophisticated with time which may erode the benefit of V2G providing this service.

Smart charging is also a competitor that could capture some of the value through managing the timing and rate at which charging occurs – similar to Apple’s approach to battery health management for their electronic devices. However, as smart charging is uni-directional, it cannot help in situations where the vehicle is parked with a full battery. In these situations, only V2G can provide realistic solutions.

Key Takeaways

V2G is entering already competitive markets, but in each case providing something slightly different which sets it apart from the rest of the market. V2G is often able to provide a lower cost solution by making use of an existing asset – the battery in someone’s EV. Yet, the bi-directional nature is also unique to V2G compared to fossil fuelled generators or smart charging.

Stationary Battery Storage is likely the major competitor to V2G as it is able to do everything V2G can do. Batteries are expensive and take up considerable space – two things V2G can help reduce. But batteries are also available all the time, while V2G is dependent on having an EV plugged in to be able to deliver any value.

So, it may not be completely clear how V2G will fair against the other options, but it is clear that it has a real opportunity to compete and provide valuable services.

What do you think?

So far, we have discussed MY views of V2G and the competing technologies. But what do YOU think are the advantages or disadvantages that V2G offers over these alternatives? Are there any other technologies competing in this space you think we have missed? Share your thoughts with us and the other learners in the discussion below.