Ins and Outs of Home EV Charging

With a number of public chargers still free and the price of EVs still high, we’re in the early days of EV charging – especially when charging at home.

EV uptake is increasing and its likely to rise steadily for years to come. Here are some guidelines around charging an EV at home.

Electric mobility is on the rise. Today, there are over 10 million registered electric vehicles on the roads, which is a significant number. A telling factor is, however, the big shift in consumer mindset we’re seeing with regards to electric cars. McKinsey & Company, for example, reports that over 45% of car owners are considering buying an EV, so the tipping point in passenger EV adoption has already been surpassed.

This isn’t surprising: electric cars are less polluting, more sustainable, and cheaper to drive than vehicles with an internal combustion engine. Depending on how you drive, it can offer a lot more convenience as well.

As electric vehicles become more common across the world, the bulk of EV charging will take place at home. However, while charging at home is convenient, the concept is also new, different, and possibly a bit overwhelming for new EV adopters.

If you’re unsure about the ins and outs of charging an EV at home, here are some guidelines to help you get started.

Installation costs, style and choice of plug

The first decision to make as an EV car owner is the cost, style and choice of charging unit. A typical style of charger is an EV ‘wall box’, which starts at around $2,500 plus fitting. Another aspect to consider is if the charger itself is fitted with a Residual Current Device (RCD), which adds an extra $500+ to the total cost.

For home use, a single-phase charger will fit easily on a wall and offer around 7kWh charging, which is six times more than a portable charger. The price of installing a home charger should be factored into the cost of buying an EV.

The plug style relates to the type of EV you own. A Type 1 covers popular cars like the Nissan Leaf and Outlander, but Type 2 plugs are increasingly becoming the global standard.

Some chargers can be linked to a smartphone app and some units also have ‘smart’ tech, that allows remote access via Bluetooth, mobile, or WiFi, as well as scheduled charging. Other charging unit features include a cable holder for neater storage, sockets for either Type 1 or Type 2 plugs, and an isolator switch for code compliance and the ability to switch it off when it’s not in use.

Cost of charging at home

The most common reason that EV owners charge their vehicles at home is convenience. While we are familiar with petrol prices fluctuating, it’s also important to remember that electricity prices increase and decrease too.

Peak electricity demand happens when most home appliances are in use, which is usually between 7am and 9 am and 5pm and 9pm. This means that energy prices can be higher at this time – depending on the plan you have with your electricity retailer.

Energy production can be more harmful to the environment during these peak times because – to create electricity quickly – it’s often generated from less renewable energy sources. This is why charging during peak times can divert you from your sustainability goals.

To get the most value from charging at home, EV owners should charge their vehicles during off-peak hours. Some electric companies even offer incentives, such as Electric Kiwi’s Hour of Power, where homeowners get access to free electricity for an hour. You can also include the optional benefit of solar charging scheduling and adapting to shifting peaks of energy demand.

Utilising a charging schedule or timer is also another option to consider. This lets you have control over your power usage, as you can set when you charge your EV and for how long.

Should you charge your EV every night?

In most cases, automatically topping up your EV every night isn’t necessarily the best practice, as this can affect the lifespan of your battery. While you may feel better leaving home in the morning knowing that you’ve got a full charge, some research shows it can shorten the lifespan of your EV’s battery pack.

According to the University of Michigan, always charging your vehicle to 100% (and even leaving it at 0%) can cause stress to the battery. One key recommendation is to keep the vehicle’s charge between 20% to 80% capacity and only charge it when necessary.

As New Zealand’s electric vehicle fleet continues to grow and customers take advantage of discounted energy rates, energy demand at night is expected to increase. Local trials are currently underway for smart chargers to automate charging schedules to help drivers adapt to changing peak demands based on electricity costs and clean energy availability.

For now, it’s recommended you research all option thoroughly before investing in a home charging station to work out which one suits your needs best and which electricity company offers the best plan.