Monday, 11 March 2019

My Electric Car - The Maths

I've now sat down and done a few back-of-the-envelope calculations. I've not had anyone check them so let me know if you see any errors and I will happily discuss my assumptions and methodology.

I have tried to be conservative in my calculations and have used the latest grid electricity CO2 emissions figures for calculating the amount of CO2 emissions my driving will generate.

Headline figures:
  • My electric car is over 400% more energy efficient than my diesel car was.
  • I will have reduced my CO2 emissions from driving by over 25% per year
  • I have reduced my fuel cost by over 70% or £2,800 per year
  • If all private cars in the UK were to go electric by 2040 we would need 2 new large nuclear facilities or 16 new large wind farms at a cost of £20 - 30 billion to power them all.
  • I drive over three times further than the average UK driver in a year.

We could all start driving electric cars, but we better get some new power stations under way and quick. £20 - 30 billion is only 2.5 - 3.5 % of the annual budget.

All the calculations used can be found in my Google Docs Spreadsheet

Wednesday, 27 February 2019

And I Could Drive One Thousand Miles

Two weeks into owning an electric car (Nissan Leaf 2018) and I've driven over 1000 miles. This is not unexpected as I have an 85 mile a day commute. On the first day of owning the car, I had definite range anxiety, but now I am relaxed and enjoying the experience.

I have not had to change my driving style too much, just reducing my speed a little on the motorway to about 70 mph :-) I'm not keen on driving and always see it as a waste of my time, but the Leaf has a nice feature called Pro Pilot that keeps me a safe distance from the car in front, at a maximum speed set by me and helps to keep you within the current lane. I make use of my time listening to audio books from Audible which makes the time spent driving feel more productive.

As expected, I have seen our home electricity use rise considerably. A daily charge takes about 5 hours at 7kWh. At a cost of 14p/kWh thats a cost of about £4.90 per day or about £25 for a weekly commute. Previously I was spending about £60 per week in diesel. As a way to keep the price of the electricity as low as possible, I have signed up with Ecotricity's EV tariff. This gives a reduced overnight tariff for owners of electric vehicles similar to economy 7.

For my next step I am going to perform a more in depth analysis of the cost differences between an EV and its diesel equivalent both in cost and emissions. I just need to capture a bit more data and find some time in my busy life.

Thursday, 7 February 2019

The road ahead

RenSMART has a plan. Not a small plan, a big plan, you might even call it an adventure, and its open for the whole world to join us in.

We started out with a plan to create a Renewable Energy Market Place (Rens Mart), the world was not quite ready for this, but as part of the process of building our business we started providing information to help people make decisions on whether to install a renewable energy system, and what specification to choose.

This has proved to be a popular service over the last couple of years. Now it is time for step 2.

Step 1 has provided a model to help estimate future energy use based on estimates and models.
Step 2 is to refine this service.

Firstly, rather than model existing energy use, we plan to help you capture the actual energy use at your location before installation.

Secondly, we will help you continue to capture this information once you have a renewable energy generation system installed and combine this information to give a real time energy use and export balance.

Thirdly we will provide you with a renewable energy forecast for the day and week ahead.

All of this will be made possible through an improved version of the RenSMART model, a software product we have been refining for some time and that will be made available as open source for wider scrutiny.

As we move forward, we will blog our progress.

Gone Electric

Background
In October 2010 I had solar panels fitted to my roof at home. Just a small installation of about 3kW peak under the Feed In Tariff, then called Clean Energy Cash Back.

At the beginning of November last year, according to my calculations, they had paid for themselves through Feed In Tariff payments, export tariff payments and the value of the electricity generated that we use ourselves.

Time for a new project. I've been looking at electric cars for a couple of years. I had several requirements that needed to be met before I could take the leap:


  • The car had to be able to complete my commute of 85 miles a day on a single charge.
  • The price had to be comparable with a mid range fossil fuel car.


The Tesla Model 3 seemed like the first car that was going to meet the requirements, so I put down a deposit and joined the queue. After six months, it seemed apparent that this car was not going to be available for some time (if ever) so I started looking at the new Nissan Leaf. In august of last year I canceled my Tesla and ordered a new Nissan Leaf. I was told it would probably take until January to arrive, and yesterday I picked it up.

My First Journey
Driving it of the forecourt of the Nissan dealership, it had almost a full charge and said about 180 miles range available. Unfortunately, I had a meeting to be at, so had to drive at motorway speeds. It appears the 180 miles range does not hold for my normal driving style. By the time I had arrived (a distance of about 40 miles) the available range had dropped to 90 miles.

In the Leaf's defence, I had had the heating on at the start of the journey, it was a cold day and I had not switched on all of the energy saving features in the car, however, without a charging point at work, I now had range anxiety. With a home journey of 45 miles and that rate of discharge, I was not sure I could make it home.

Unluckily the day I had chosen to pick up the car was also the coldest day of the year so far and the first day of snow, however, as I knew that I was on the edge of the range that the car seemed likely to make, I decided to go without heating. Still, as I made my way home the range was reducing at about double the miles I was doing.

Part of my journey home takes me on to the M4, and looking at the map of charging point, I saw that there were several provided at a service station I would be passing. I thought if I made a short stop I could top up the battery enough to get home.
I had already ready installed the Ecotricity Electric Highway app and thought this would be a painless process but no. I found the charging points easily enough, pulled in and opened the app on my phone. It hung. Just the initial splash screen. I closed it and tried again, same result. I rebooted the phone, no luck. So in the end I gave up and decided to take the chance I may run out of charge before home.

Once off the M4, I turned on all of the eco options in the car. At the lower speeds and with these options switched on, the miles started to match the range and it looked like I may make it.
By the time I was 10 miles from home with 25 miles range left, I finally felt confident enough to turn on the heating. I made it home with about 20% battery remaining.

Now a day later, how do I feel ?
I think driving is going to be different. This is not a like for like swap with my old diesel Volvo.
I will have to take more notice of my driving style and I will reserve judgement on whether the move to an EV was a good idea until I have made a few more trips and compare my electricity bill increase with the decrease in my car fuel bill.


Monday, 14 January 2013

A New Blog For RenSMART

I have been using my personal blog to make comments on RenSMART's progress until now, but have decided that it is time RenSMART had it's own blog so here it is.
We are in the process of creating a plan for the year ahead, there are several projects in the pipeline, and  some of those will go live soon.
If you have any ideas of projects you would like us to consider, please let us know at information@rensmart.com.

May your year be fruitful and your carbon footprint reduced.
Nik Cross and the RenSMART team.