Daily Archives: June 21, 2017

Home charging a Nissan Leaf (Image: Nissan)

Charging an Electric Car: How it is Nothing Like Refuelling a Petrol or Diesel Car

People who have never owned an electric car don’t understand how different charging one is compared to fuelling a petrol or diesel car. Therefore I’m going to explain what charging an electric car is like so that potential owners can understand it better.

Home charging a Nissan Leaf (Image: Nissan)
Home charging a Nissan Leaf (Image: Nissan)

The point I want to get across is that charging an electric car is much easier and more convenient than filling a fossil-fuelled car. That’s an idea that can be difficult to grasp. Now that I’ve upgraded to electric (I’m on my second all-electric car) I could never go back, any more than I’d give up my smartphone and make do with a landline.

Here I’ll concentrate on the ins and outs of home refuelling, and cover charging away from home another time.

Charging System

Most electric cars come with a charging cable (fitted with a 13 Amp plug) that can be used to charge the car; such cables can be bought separately where they are not supplied with the car. One name given to these items is ‘granny cable’ as they can also be used to charge up while visiting relatives.

BMW i3 ‘occasional use’ charging cable (Image: BMW)
BMW i3 ‘occasional use’ charging cable (Image: BMW)

Another name they are given is ‘occasional use cable’ as they are not intended to be used frequently. They will also be slow to charge the car (12 hours or more) as a standard home socket is not capable of providing as much power as the car can potentially take.

Instead most car owners will have a special charge point installed at home to charge their car. This often comes free with a new car. It is typically wired straight into the main house consumer unit. It will be capable of passing higher power than a standard socket – usually either 16 or 32 Amps – and will be designed for frequent use.

Using a third-party ZOE granny cable while visiting my brother (Image: T. Larkum)
Using a third-party ZOE granny cable while visiting my brother (Image: T. Larkum)

These charge points can be installed either inside a garage, or on a garage or other outside wall. Sometimes they’re just put on a post beside the driveway. They are all waterproofed and can be used in all weathers (including heavy rain). They usually come fitted with a tethered cable to match the car but sometimes just have a socket to which the owner can connect different cables, for example if the unit has to charge electric cars with different types of connector. The pros and cons of having a tethered versus untethered charge point are covered elsewhere.

Charging an Electric Car: Frequency

How often does an electric car need to be charged? This is an important question, and is key to why charging is more convenient than conventional refuelling.

The obvious answer, at least to someone used to a conventional car, would be “when it’s empty”. That’s because most people let their cars run low on fuel before refilling. There is no good reason for this; it simply reflects the fact that conventional refuelling is so inconvenient that it is to be avoided whenever possible. It takes time, and usually also involves a diversion from where you actually want to go.

With an electric car you could choose to do the same thing, relying on public charge points, and that can work if you can’t do home charging. However for the majority of electric car owners with a home charge point the easiest thing is simply to charge at home overnight every night.

Charging a Renault ZOE on the drive (Image: Fraunhofer ISE)
Charging a Renault ZOE on the drive (Image: Fraunhofer ISE)

Electric cars use Lithium-Ion batteries, similar to those found in mobile phones (though they have significantly more sophisticated charge management systems than phones and so last longer). Lithium-Ion likes to be kept charged unlike previous technologies (e.g. Nickel-Cadmium batteries) that you were supposed to run down before recharging. Therefore it does no harm to plug in every night and so have the car battery fully charged every morning ready to go.

Using a dedicated high power charge point allows a typical electric car to be charged in about 4 hours. It’s also fine to only partly refill it. Therefore it can be perfectly practical to drive, say 100 miles during the day for work, then go home and – those evenings when it’s useful – top it up for an hour or two and go out again for, say, another 50 miles.

Charging an Electric Car: Process

It’s very easy to charge an electric car once you have a dedicated charge point. If you are lazy, like me, then you have a tethered one with its cable permanently attached so you don’t have to unpack a cable each time. Similarly, I choose to leave mine switched on permanently for convenience.

In this case, charging is as simple as the following:

  • Open the charge point door on the car
  • Uncurl just enough of the charge cable to insert its connector into the car’s charge socket

The car will automatically start to charge when it sees the electrical connection made. It will control the charge and finish it automatically.

On my original Renault ZOE the charge point door was unlocked using a button on the key fob or a switch inside the car. The charge socket was in the nose and so required walking around to it to insert the connector. The total time taken was about 15 seconds; this would also be typical for the Nissan Leaf.

Charging a Nissan Leaf in the garage (Image: Chargemasterplc.com)
Charging a Nissan Leaf in the garage (Image: Chargemasterplc.com)

On my current BMW i3 the charge point door is always unlocked if the car is unlocked, and the charge socket is on the driver’s side. Therefore I can insert the connector after I have parked the car and as I walk out of the garage; there is literally no additional time taken to set the car for charging. The Hyundai IONIQ Electric also has the socket on the rear quarter, though on the passenger side.

Charging a BMW i3 on the drive (Image: BMW)
Charging a BMW i3 on the drive (Image: BMW)

People sometimes ask me how long it takes to charge my car. They probably expect to hear me say ‘4 hours’ or whatever, but actually it takes me personally no time at all, not a single minute. That’s because I don’t care how long it takes for the battery to fill up while I’m in the house (and probably asleep).

Charging a Hyundai IONIQ Electric on the drive (Image: T. Heale)
Charging a Hyundai IONIQ Electric on the drive (Image: T. Heale)

With my i3 having a range of about 120 miles, and my commute being 45 miles, it’s not even a problem if I forget to charge for a day or two. However, like with your smartphone, making charging it a daily routine is generally the best option.

Summary

One of the great things I love about a car that’s electric is no longer having to spend time fuelling it. It’s just 100% full every morning when I get in, as if by magic. I certainly don’t miss having to travel to petrol stations, often standing in the dark and rain, to hand over large amounts of money.

Now instead I fuel the car myself using renewable energy. During the week I charge it from wind (courtesy of our renewable electricity supplier) and a fill-up costs about £2.50. At the weekend I can charge it from our solar panels for free.

What difference will electric cars make to our electricity demand

Simple calculation[s] as to the impact on electricity demand as we progressively switch over to electric cars.

National Grid estimates up to 7% increase in electricity demand by 2040 for EVs

There are around 30 million cars on the road today [1]. National Grid’s Future Energy Scenarios 2016 presents 4 scenarios – in the most ambitious ‘Gone Green’ scenario there are 9.7 million electric vehicles (EV) on the roads in 2040 using an extra 24 TWh/year. Relative to current electricity demand that is an increase of 7%[2].

But the impact on peak demand will be minor, if drivers respond to time of use pricing.

However, this demand is highly unlikely to be spread evenly through the day and year. Firstly, people tend to drive more in the summer, presumably because it is considerably more pleasant than driving in the winter [3]. Fortunately our peak electricity demand is in the winter so this helps to even out the load.

Secondly, assuming time of use pricing is widely adopted drivers will try quite hard to charge their vehicles at times of the day when the electricity is cheap. Most people will have quite a lot of flexibility and during the peak time a lot of drivers are on the road anyway.

This means electric car charging will increase non-peak demand much more than peak. The chart below shows a typical January day. If electric car charging is spread over non-peak times it will start to fill in the yellow area but not impact on the peak demand. 24 TWh/year is 66 GWh/day so it could fill in just over a quarter of the yellow area.
A typical day’s UK electricity demand in January

If all cars were electric there would be more impact on peak demand

However, 66 TWh/day is from only 9.7 million electric vehicles. If we replaced all 30 million cars, it would be nearer 200 GWh/day. This does still fit into the yellow area – just – but it would be quite a challenge to ensure that there was no ‘leakage’ and it did not impact on the winter peak at all.

Read more: Blogspot

Severe Flooding, Against a Background of Wind Turbines: November 2012, Tyringham, Bucks. (Image: T. Larkum)

Scientists say the pace of sea level rise has nearly tripled since 1990

A new scientific analysis finds that the Earth’s oceans are rising nearly three times as rapidly as they were throughout most of the 20th century, one of the strongest indications yet that a much feared trend of not just sea level rise, but its acceleration, is now underway.

Severe Flooding, Against a Background of Wind Turbines: November 2012, Tyringham, Bucks. (Image: T. Larkum)
Severe Flooding, Against a Background of Wind Turbines (Image: T. Larkum)

“We have a much stronger acceleration in sea level rise than formerly thought,”

said Sönke Dangendorf, a researcher with the University of Siegen in Germany who led the study along with scientists at institutions in Spain, France, Norway and the Netherlands.

Their paper, just out in the Proceedings of the National Academy of Sciences, isn’t the first to find that the rate of rising seas is itself increasing — but it finds a bigger rate of increase than in past studies. The new paper concludes that before 1990, oceans were rising at about 1.1 millimeters per year, or just 0.43 inches per decade. From 1993 through 2012, though, it finds that they rose at 3.1 millimeters per year, or 1.22 inches per decade.

The cause, said Dangendorf, is that sea level rise throughout much of the 20th century was driven by the melting of land-based glaciers and the expansion of seawater as it warms, but sea level rise in the 21st century has now, on top of that, added in major contributions from the ice sheets of Greenland and Antarctica.

“The sea level rise is now three times as fast as before 1990,”

Dangendorf said.

Studying the changing rate of sea level rise is complicated by the fact that scientists only have a precise satellite record of its rate going back to the early 1990s. Before that, the records rely on tide gauges spread around the world in various locations.

But sea level rise varies widely in different places, due to the rising and sinking of land, large-scale gravitational effects on the waters of the globe and other local factors.

Read more: The Washington Post