How an EV can slash your power bill

Household power bills are going through the roof as a result of increased energy prices.

Ironically, battery-powered cars could provide a solution that not only slashes your electricity bill but could also earn you money.

You see, electric cars – as a collective and individually – have the potential to be plugged into the national energy grid as an additional power source through what’s termed vehicle-to-grid (V2G) technology.

Basically, this allows the electricity stored in an EV’s battery to be used as a supplementary source to your household power supply, either as a back-up in an emergency situation such as a blackout or on a schedule that piggybacks into the grid that reduces your reliance on the main supply.

Vehicle-to-grid technology creates an ecosystem that employs electric vehicles as an additional energy source to local and national electricity networks.

V2G essentially monitors the charging and discharging of EV batteries in accordance to consumer needs. When the production of renewable energy exceeds demand, such as during the middle of the day when solar power generators are working at their highest output, electric cars plugged into the network will be recharged to their maximum capacity.

At the opposite end of the spectrum, during peak periods of electricity demand – like at night when households are fully occupied – the energy stored in an EV battery can be used to power the house or be returned to the grid.

Using the vehicle’s on-board battery management system, users can ensure the battery has enough charge remaining to commute to work where the battery can be replenished again, thereby creating a continuous cycle that optimises the production and distribution of cleaner, renewable energy sources.

Only a handful of electric vehicles currently on sale in Australia have vehicle-to-grid capabilities: the Nissan LEAF and the Mitsubishi Outlander and Mitsubishi Eclipse Cross plug-in hybrids.

V2G is currently only supported by vehicles equipped with a CHAdeMo-type charging plug, which are predominantly used by Japanese car-makers. Lobbyists are calling for a global standardisation of electric vehicle charging infrastructure to ensure the wider availability of V2G in the future.

Other car-makers such as the Volkswagen Group, Mercedes-Benz and Polestar are working on introducing the technology with upcoming electric vehicles.

In any case, for V2G to work it requires a unique two-way household charger that allows the bi-directional flow of electricity to and from the vehicle’s battery.

Like any new technology, these are not cheap, costing approximately $10,000 plus installation, with JET Charge currently the only supplier in Australia – and in limited quantities to households.

JET Charge expects availability will improve and the price will drop exponentially as demand for V2G chargers increases when more car-makers adopt the technology.

Other vehicles, like the Hyundai IONIQ 5 and Kia EV6, have vehicle-to-load (V2L) capabilities, which means they can be used as a portable power station and provide 240V electricity to appliances and other electrical devices via a conventional household power point adaptor.

This means users can plug in power tools, camping equipment and the like remotely. But they do not have the same ability to deliver power back to the household grid.

That all depends on how much power you currently use, and the size of the battery in your EV.

But, in a utopian world, your house, workplace and car would interact to become a standalone renewable power source.

With enough solar panels on the roof at home and at work, an EV could be recharged using fully renewable energy while it is parked in the garage during the day. That energy could then be used to power the vehicle for its daily commute as well as the house at night.

Considering the average daily electricity consumption for an Australian household is around 13.7kWh, and the battery storage capacity in full EVs currently ranges between 39-100kWh, it is entirely feasible that all EVs on sale now have the ability to hold enough electricity to power a home each day.

That means you could potentially eliminate power bills completely. Right now!

However, by delivering more power back to the grid than you use each day, V2G technology could also allow you to flip the switch (pun intended) on your relationship with an energy provider and become a supplier rather than just a customer.

As a hypothetical example, first of all let’s consider you have a north-facing 7kW solar panel system at home/office that, according to research by the Clean Energy Council, produces on average 28kWh of electricity each day if you live in Sydney (or fractionally less in Melbourne and slightly more in most other major metropolitan areas in Australia).

For starters, that’s more than double the average daily household consumption, which means you’re way ahead.

Now, let’s work out how much energy is required to drive an EV to work and back. If you consider the average daily round-trip commute is 37km and the average energy consumption for electric vehicles is around 15kWh/100km, you’ll need 5-6kWh to drive an EV to work and back.

That means you will likely have an average daily consumption of around 20kWh and, therefore, a surplus of 8kWh.

If we can assume that energy providers will buy back electricity at the same price they sell it for (around 20c/kWh) then that means you’re getting free household power and free fuel, plus earning more than $1/day.

Now that doesn’t sound like much in the grand scheme of things, but if you add the $365 you’ll make to the approximate $1500 in savings each year for power alone, and more than $1000 per year you don’t have to pay for petrol costs, the investment in a solar system, EV and the V2G charger would pay for themselves in less than a decade.

After that, you’ve got free renewable energy for ‘life’. And, with V2G, so does the rest of the country.

There are a few barriers in place to employing vehicle-to-grid technology.

Firstly, the continuous recharging and discharging of the EV battery increases the charge cycle rate, which has an adverse effect on battery longevity.

Battery packs naturally degrade over time as the chemical make-up of the cathodes in each individual cell breaks down due to the stresses of heat generated when receiving and providing electricity.

The end result is the battery loses storage capacity, which reduces the driving range.

Secondly, households need to have smart meters installed that monitor the demand and supply of electricity to effectively use V2G as a viable power source to the network.

Lastly, according to the Realising Electric Vehicle-to-grid Services (REVS) program conducted by the Australian National University under Dr Kathyrn Lucas-Healy, which is using a fleet of 51 Nissan LEAF EVs in a real-world trial throughout Canberra, government needs to implement a raft of regulations and industry standards within the energy sector that ensures the proper use of V2G technology and provide clear guidelines with pricing structures for households as both consumers and suppliers.

It also claims the government needs to foster a diverse group of existing companies and new start-ups with incentives to encourage investment in V2G technology and fund pilot programs to showcase the benefits.

All said and done, while vehicle-to-grid technology is already here, there is a long way to go before it becomes part of our everyday life.

But, with the cost of living increasing at an alarming rate, investing in an EV with V2G along with solar power on your house today could save you thousands in the end. And help the planet too.

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