How Long Will It Take to Charge My EV From Home?
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One of the most common questions people ask when they consider switching to electric vehicles (EVs) is, "How long will it take to charge my EV at home?" The answer depends on several factors, including your vehicle's battery capacity, your home's power supply and your charger type.
Battery Capacity
Knowing your battery size is the first step in estimating charging time. Your EV's battery capacity is measured in kilowatt-hours (kWh). A higher-capacity battery will take longer to charge than a smaller one.
For example, a small EV like a Nissan Leaf will have a battery capacity of around 40 kWh, whereas larger models, such as a Tesla Model Y, can have batteries exceeding 75 kWh.
Your Home's Electrical Supply
Your home's electrical supply also affects charging times. The vast majority of UK homes operate on a single-phase power supply, which supports chargers up to 7 kW. However, some properties have a three-phase power supply, enabling faster chargers up to 22 kW.
Home Charger
The final key factor to help determine how long it will take to charge your electric vehicle from home is the type of home charging setup you have.
If you have a single-phase power supply with a dedicated home charger, the typical output is 7kW. With such a charger, a 40 kWh battery can be charged in approximately 6-8 hours and a 75 kWh battery in 10-12 hours.
The charging time can be estimated using this simple formula:
Vehicle Battery Capacity (kWh) / Charger Speed (kW) = Time to Charge (hours)
It is important to ensure that your dedicated home charger is installed professionally as the installer will be able to ensure that your existing electrical installation is suitable for the significant load required charge your electric vehicle. The installer will also be able to ensure that the charger is installed in compliance with electrical and building regulations, including for example PEN protection requirements, and provide you with an compliance certificate on completion.
While it possible to charge your vehicle using a standard 3-pin plug socket also known as a ‘granny charger’, we don’t recommend using them except in the case of an emergency. Standard 3-pin plug sockets don’t provide the protection normally afforded by dedicated chargers. Even if they have a PEN protection device, granny chargers are still run permanently at 100% load, which is not the sort of load normally expected on 13A house sockets. They are also three times slower than a 7kW dedicated charger, so the charging times are unpractical.
Other Factors that Influence Charging Speed
Several additional factors can affect how long it takes to charge your EV. The main ones are:
- State of Charge (SOC): The time needed depends on how much charge your battery has when you start the charge. Topping up from 50% will be faster than charging from empty.
- Weather conditions: Cold temperatures can slow charging speed, as EV batteries are less efficient in low temperatures. Some vehicles have pre-conditioning features to warm the battery before charging.
- Charger efficiency: All chargers lose energy during the process, typically around 10%. To minimise this loss, opt for high-quality chargers.
Maximising Your Charging
Here are some tips to make your home charging setup as efficient as possible:
- Install a smart charger: Smart chargers allow you to monitor energy usage, set charging schedules, and optimise charging speeds.
- Charge overnight: Electricity rates are often lower at night, making it a cost-effective time to charge.
- Pre-condition your EV: Use your EV's pre-conditioning feature to optimise the battery temperature before charging in cold weather.
- Keep your charger in good condition: Regular maintenance ensures your charger operates efficiently and safely.
Charging your EV at home is a convenient and cost-effective way to keep your vehicle ready to go. While charging times vary based on battery size, charger type, and electrical supply, investing in a dedicated home charger will make a significant difference. With the correct setup, you can ensure your EV is fully charged and waiting for you each morning.
If you are worried about getting an EV because you only have street parking, then check out our solution which provides safe and secure on-street EV charging. You can still reap all the benefits of home charging without a driveway.