Kia ora koutou
December’s 1-click survey and data analysis featured electricity prices and your response to the overnight discounts for charging your electric vehicles and plug-in hybrids. We focused on these themes because we noticed how much your electricity prices varied.
Only 24% of the respondents to the 1-click survey are already on cheaper night time rates for charging their EV or PHEV. Of the remainder, 44% answered ‘Definitely yes’ or ‘Probably yes’ to the proposition i.e. “I am likely to switch my electricity supplier to one that offers night-time discounts for EV / PHEV owners”. Combining these figures suggest that around two thirds of New Zealand Zealand’s electric vehicle and plug-in hybrid owners either already have, or are likely to take up a night-time discounted electricity contract if it were offered by their supplier. For others, overall household demand and a need to integrate vehicle charging with home solar generation make other forms of discounted supply contracts more attractive. Using electricity generated from renewable source and drawing electricity late at night to relieve pressure on the national grid are also important considerations for some EV and PHEV owners. Some owners are actively searching for cheaper electricity deals, whereas others consider the cost of electricity to be a minor consideration – one referred to the cost of charging as “peanuts” – see http://flipthefleet.org/2017/1-click-survey-14/ for a full record of your personal testimonies.
The price for electricity used for charging at home or work was provided for 402 of the 504 vehicles which were registered in Flip the Fleet over the past year
- Cost varied from 4 c/kWh all the way up to 45 c/kWh. 82% of the vehicles are charged at between 11 c/kWh and 30 c/kWh (see Fig. 1).
- The average price was 20.4 c/kWh.
- Assuming that around 20% of the electricity drawn is lost as heat when charging your vehicle, and applying an average efficiency of transport (6.6 km/kWh), we predict that EV and PHEV owners are spending on average about 4 c/km on electricity.
- This will overestimate the average cost because we have deliberately used a pessimistic estimate (20%) of wasted electricity during charging. Also, some owners: (a) use the ‘free hour’ for your charging off-peak; (b) have solar panels or windmills; (c) charge at work; or (d) have access to free rapid chargers nearby.
We will have better cost estimates next year, but these preliminary values suggest that some claims of low costs of running EVs that we have seen in the media and social networks (e.g. 1 or 2 c/km) are exaggerating their benefits, at least for the average EV owner. Certainly, electricity is not a trivial part of transport costs for many owners. Let’s not lose credibility by exaggerating our case until we have the firm data to back up our claims, even though of course we can already show that EVs are much cheaper than running an equivalent sized internal combustion vehicle.
In the meantime, it’s the tenfold variation in electricity price that is startling. Many of us may be able to get a cheaper deal if we shop around and can optimise our whole household electricity use and manage the time we charge our EVs. There is a win:win:win here for us as EV owners, New Zealanders in general, and for the environment – if we can spread our electricity demand to avoid the morning and evening domestic demand peaks, we should end up with even cheaper transport, reduce costs of electricity infrastructure, and reduce greenhouse gas emissions by minimising the use of fossil fueled power plants that are needed mainly during the peak demand periods.
Repairs and maintenance data please: A top priority in 2018 will be to estimate the repairs and maintenance costs of EVs, PHEVs and equivalent Internal Combustion Vehicles (ICVs). We think this is the biggest info gap about EVs in New Zealand and overseas, and reckon it is in the ballpark of contributing a third of your overall savings from EVs. Therefore, we have two requests:
- Please upload any historical data for repairs and maintenance that you might have for your EVs or PHEVs. We think that many of you started filling in the full monthly records to Flip the Fleet at the time of enrolment (rather than from the first month of your ownership of your vehicle) because you lacked the detailed odometer readings etc. for the earlier months. If you have data for any expenditure, or a complete recollection of there being no repairs and maintenance in those earlier months, please back load the data to help the statistical reliability of our analysis. It’s easy to upload the historical data – you just hit the ‘Add Data’ button in the normal way and select the historical month from the drop-down list at the top. Put the $ amount and if possible a description of the repairs done, or a zero in each month if you know no repairs or maintenance costs were occurred (a blank field is just ignored, so we need a zero there to confirm that no costs occurred). Then hit the submit button (no other data are needed).
- Please help us locate some ICV repairs and maintenance data for comparison: i.e. if possible, please provide firstname.lastname@example.org contact details for any friends, colleagues or associates that will have a database (or accounting records) of ICVs that we could use for comparison. A local garage, or a set of fleet records would be ideal.
Rapid charger survey underway: We are using an online “choice experiment” approach from economics to learn what you most want when visiting rapid chargers. It leads on to a survey of how often you end up having to wait to access the charger, whether you commonly get ICEd etc. The method will be able rank any number of potential sites for rapid chargers in a neighbourhood, so your results can be applied later to benefit the whole EV community. So far 45 EV owners have completed the survey (thanks!), but we need lots more to make it statistically reliable. Please join in if you have got 15-20 minutes to spare by clicking the following link: http://www.1000minds.com/go/Rapid-Chargers-10Dec17
This month’s hint to get the most out of Flip the Fleet’s dashboard: Hover your mouse over each of the data markers or bars to read the exact numeric value.
Cheers– drive your battery safely this Christmas!
Dima and Henrik