Electric vehicle summer experience
When the MG ZS electric vehicle joined Libby’s Nissan LEAF in the carport earlier this year, we completed the transition to an all-electric household. That event marked an important milestone in our journey towards a more sustainable lifestyle.
Of course, family and friends were curious about how owning EVs affected our lives. Questions were asked.
Short answers to big electric vehicle questions.
How far can you go? All the way to Brisbane if I wanted. The MG ZS EV has a design range of 263 km which is a decent drive. However, I can drive much further using my trusty Plugshare and Chargefox apps to leapfrog from one DC fast charger station to another.
How long does it take to charge an electric vehicle? As another EV owner cheekily observed, it only takes a few seconds to charge. That’s the time required to plug and unplug the charging cable when the car is sitting in the garage at home. What people really want to know is how long it’s connected to a charger. At home, I regularly trickle charge for a few hours during the day. For a major recharge needed in a hurry, I’ll spend 20-30 minutes relaxing at a Chargefox 50kW fast charger.
What’s the cost for charging an electric vehicle? Nothing really since we used home-grown solar power made during long, sunny summer days. When George Gershwin wrote “Summertime and the livin’ is easy,” he didn’t have solar power systems in mind. However, George’s lyrics matched my experience with EV charging in summer.
Now for anyone interested, here are the details. While I explain, remember that other EV owners will have different experiences. Many factors contribute to how well an electric vehicle integrates into daily life.
How far can an electric vehicle go?
Libby has a 2011 Nissan LEAF carrying a 24 kWh battery. After 70,000 km and 10 years, the effective driving range dropped from the 115 km design to 80 km at a stretch. Given its limited range, the LEAF is an exclusively urban vehicle. It’s great for local shopping trips or excursions to the Melbourne CBD.
My 2020 MG ZS EV has a 44.5 kWh battery. The WLTP driving range is 263 km. The MG is obviously our vehicle of choice for longer distances such as a 120 km round trip to visit family in Melbourne’s western suburbs.
In general, we don’t drive many kilometres in a week. For example, neither of us have a daily work commute. An electric vehicle that can go for 263 km between charges is more than enough for our needs around town. It would be very unusual for us to drain the MGs battery in one day, then have to recharge it overnight for a long drive the next day.
Driving further afield.
Getting out of Melbourne requires planning with the Plugshare app. Plugshare shows me the locations and status of 50 kW DC fast chargers anywhere in Australia. They’re called fast chargers because they can transfer up to 50 kW per hour into a car’s battery. It takes about 30 minutes to take the MG from 20% to 80%. Most of the ones I use belong to Chargefox which has a handy app for easily connecting to the charger when I arrive. Some EV owners can take advantage of 350 kW ultra-rapid chargers which are appearing all over Australia. I can’t because the MG has a 50 kW limit.
The apps show I could drive to Brisbane by hopping from fast charger to fast charger. The biggest hop is 165 km which is doable with the MG, even after accounting for steady cruising at highway speeds.
Visiting a friends’ Inverloch holiday house was our first test of driving a longer distance. Before we left, I charged the battery to 100% at home. Just before Inverloch, we stopped for 20 minutes at the fast charger in Cape Paterson for a refill to 80%. A big thank you to The Cape development for providing free electricity. Before returning home, I simply paid another visit to The Cape’s charger to ensure the electric vehicle had plenty of juice for the journey. Easy, peasy.
What’s the cost for charging an electric vehicle?
During summer and early autumn, our electricity bill didn’t increase due to electric vehicle charging. Look for the condition in that statement. The winter experience is probably going to be different for reasons I’ll explain in a later blog post.
Now, why didn’t the power bill jump? Hold on because this takes a bit of explaining.
Not regularly driving long distances is a significant factor. Most of the goods and services we need are either within walking distance or a short drive away. That was a key factor in Libby’s choice of our home’s location. Another reason was the site’s north-south orientation, ideal for passive solar design. I should also mention a third reason – we could afford it.
Not driving long distances limits the increase in electricity consumption. But, I said the electricity bill didn’t jump. What’s going on? Essentially, we used home-grown solar power to charge the cars.
In summer, the 8kW solar array generates more electricity than the house needs. Passive solar design means we don’t need to run the reverse cycle air conditioner often to stay comfortable indoors. Even if it’s required, the high efficiency keeps energy demand low. The other large energy user in a typical house, the hot water system, is also a high efficiency heat pump programmed to run during the middle of the day. Our water is heated by solar energy.
As the following February data shows, low demand plus summer’s generating capacity equals plenty of electricity to go around. There’s enough to supply our home, fill the 10 kWh home battery for night-time use, regularly trickle charge the cars and still have excess to export.
Costs and benefits from solar charging EVs
Diverting solar power from the grid into an electric vehicle “costs” us 10c per kWh that would otherwise be income from exporting. I’m paying a “fuel” cost of $1.50 per 100 km for the MG EV. Compare that to the petrol engine MG ZS using 7 litres of petrol. Paying $1.50/L for ULP gives a rough cost of $10 to travel 100 km. Therefore, driving an EV is a significant saving, from $10 down to $1.50 for every 100 km driven.
More importantly, we’re using renewable energy. No fossil fuels were burned to generate the electricity we use to drive our cars.
How long does it take to charge an electric vehicle?
At home, we use trickle charging. Trickle charging is exactly what the name implies. The car is plugged into a household socket and draws electricity at a low rate. Libby trickle charges the LEAF from a 15A circuit at 2.5 to 3 kW. That’s a bit more than running an electric kettle. My MG is even less, drawing between 1.5 and 2 kW.
Our SolarEdge inverter is good for 6+ kW so it easily handles the usual household loads plus trickle charging an EV. There’s no worry about pushing the system past a supply limit.
Now to address the time question. Putting 40 kWh into the MG battery with a 1.5 kW supply is going to take a long time, something like 30 hours to fully charge. Fortunately, short trips mean we treat the cars like mobile phones when it comes to charging. Plug them in whenever the opportunity arises to keep the battery just right – not too full and not too empty. A few hours every day usually keeps the battery between 25 and 75% full.
Slow charging time might become an issue in the future if our driving patterns change. However, there is the option to install a 7 kW home charger system. Not yet though. I’m going to see how far we can get with trickle charging before deciding to spend money on a home charger.
Lessons learned.
An electric vehicle is a good fit with our current lifestyle. We don’t feel restricted by range anxiety. Sure, some planning is required for longer trips but, as the number of charging stations steadily increases, this is less and less of an issue.
In summer, we charged the EVs using excess electricity generated by our solar array. An excess is available because our home’s embedded sustainability design principles keep the energy demand small.
Using solar power to charge the EVs minimised our transport carbon footprint, as well as the “fuel” cost.
What’s next?
Shorter, cloudier winter days will reduce the amount of solar power available to charge the cars at home.
Can we continue with trickle charging an electric vehicle from the solar array? If not, where will the electricity come from? Do we need to install a 7 kW home charger?
Fear not, I’m going to find out and let you know.
