Choosing the Right EV Charger Speed for Your Home

Understanding EV Charger Speeds

Choosing the right charger speed depends on your electricity supply, driving habits, and budget. Here's how to decide.

Charger Speed Options

3.6kW Chargers

Charging speed:

• Adds ~10-15 miles per hour
• Full charge overnight (8-12 hours)

Best for:

• Plug-in hybrids (smaller batteries)
• Low daily mileage (<30 miles)
• Older properties with limited supply

Pros:

• Cheapest to buy and install
• No supply upgrade needed
• Lower running cost

Cons:

• Slow for full EVs
• May not complete overnight charge for large batteries

7kW Chargers (Most Popular)

Charging speed:

• Adds ~25-30 miles per hour
• Full charge typically 6-8 hours

Best for:

• Most single-phase homes
• Average daily mileage (30-60 miles)
• Standard EVs (40-80kWh batteries)

Pros:

• Good balance of speed and cost
• Works with standard single-phase supply
• Completes full charge overnight

Cons:

• May need supply upgrade in older homes
• Not the fastest option

22kW Chargers

Charging speed:

• Adds ~75-100 miles per hour
• Full charge in 2-3 hours

Best for:

• Three-phase electricity supplies
• High daily mileage (100+ miles)
• Businesses and fleet charging

Pros:

• Very fast home charging
• Ideal for quick turnarounds

Cons:

• Requires three-phase supply (most homes don't have this)
• Higher installation cost
• Many EVs can't charge faster than 7kW anyway

Understanding Your Electricity Supply

Single-Phase (Most Homes)

• Standard UK domestic supply
• 100A main fuse typical
• Maximum 7kW charger usually
• May support 11kW with assessment

Three-Phase (Some Larger Properties)

• Usually commercial or large homes
• 3x 100A phases
• Can support 22kW chargers
• Check with DNO for availability

Checking Your Supply

Look at your main fuse:

• 60A or below: May need upgrade for 7kW
• 80A: Usually fine for 7kW
• 100A: Comfortable for 7kW

We assess this during our free survey

Does Your Car Limit Charging Speed?

Many EVs have onboard charger limits:

Key point: Installing a 22kW charger with a 7kW-limited car won't charge any faster.

Cost Comparison

Excludes any supply upgrade costs

Real-World Charging Times

Assuming 60kWh battery from 20% to 80%:

Our Recommendation

For most Devon homeowners:

• 7kW charger - best value and covers 95% of needs
• Smart charger - schedule off-peak charging
• Untethered - flexible for future car changes

Consider 22kW if:

• You definitely have three-phase supply
• Your EV supports 22kW AC charging
• You regularly need fast home top-ups

Smart Features Worth Having

• Scheduling - charge during cheap Octopus Go hours
• Load balancing - prevents tripping your supply
• Solar integration - charge from your panels
• App control - monitor and manage remotely
• Energy tracking - see exactly what you use

Frequently Asked Questions

Can I upgrade my charger later?

Yes, but it's more cost-effective to install the right one first.

Will a 7kW charger damage my car?

No. The car only draws what it can accept.

Do I need three-phase for a 7kW charger?

No. 7kW works fine on single-phase.

What about rapid chargers at home?

Not practical - they require three-phase and huge supply.

Need help choosing an EV charger in Devon? Call Grant's Electrical Solutions on 01626 374 059 for a free survey and advice.