Showing posts with label power consumption. Show all posts
Showing posts with label power consumption. Show all posts

Saturday, 9 April 2011

Power consumption in winter

Deutsche Version
As a MINI E driver you realize that spring has arrived in Germany not only on the birds chirping and the green again nature. There are also the range of the car and the stability of the indicated range that make you feel happy.
Indicated range at a full charge is about 160km again and with for example SoC going down to 50% the estimated range behaves more predictible than during winter.
In winter usually indicated range at full charge was below 120km and with a SoC of about 50% even short trips of 20km became an intense experience.

Normally I try to use a public charging station at my place of work. But this charging station does not show the amount of energy the car took. Additionally I did not log the odometer every time I used my private wallbox. But there are a few charging operations, where I have written down the distance travelled and the amount of energy.



The Homepage of the MINI E reports an average power consumption of 14 to 17 kWh/100km.

With temperatures below 0°C in the winter, a cold battery with decreased power, activated cabin heater (to generate at least a tepid breeze) and switched on headlights you double the official value without difficulty.

Mostly you achieve values between 26 and 32 kWh/100km.

The final value of 22,5 kWh/100km is probably due to the significant increased ambient temperatures.

I'm curious to see what values I can achieve at ideal ambient temperatures during the last three month of the project...

Friday, 21 January 2011

Standby power consumption

Deutsche Version
To have an idea, what is the standby power consumption of the wallbox and the car, I watched the electric meter that was installed with the new power cable feeding the wallbox in the garage. 
Due to the electric meter switches digitally in 0,1kWh-steps and I do not have higher sophisticated measuring equipment, this is not more than an estimated conclusion.

Monitoring the electric meter for several days without pluging in the car shows a power consumption of 0,1kWh/24h. This may be slightly more because of  the digital switch.
So the Siemens wallbox has a standby power consumption of about 4,2 Watt (or slightly more).
This is not a big value, but projected to the period I use the MINI E (9 1/2 month, 285 days) this means 285x0,1kWh = 28,5kWh. This is equal to a full charge of MINI Es usable battery capacity of about 28kWh. At a price of 0,207 Euro/kWh this is about 5,90 Euro for the powering of the wallbox during the test period.
Integrating some smart grid features, the power consumption may rise and developers and customers should have an eye on this.
Whenever I do not need the wallbox for a longer time, I shut it off via the circuit breaker.

Monitoring the electric meter with the car plugged in after achieving a SOC of 100% and the flashing charging light is gone, the effect is the same: 0,1kWh/24h combined consumption of wallbox and fully charged car.
So it seems that the MINI E has a negligible power consumption when it is fully charged and there is no need to plug it off to avoid some extra cost.
 
Siemens Wallbox with plugged in MINI E.

This issue changes with the next generation electric vehicles providing thermal management of the battery pack and preconditioning of the cabin.

I hope the driver may choose from different scenarios ranging
... from full range priority providing optimum battery temperature and fully conditioned cabin neglecting the energy consumption
... to an eco mode with priority to minium energy consumption providing just in time battery temperature sufficient for using the regenerative brake and a moderate cabin temperature.

Tuesday, 14 December 2010

MINI E in the snow

Deutsche Version

At the weekend I visited my parents again. After a 71km trip the charge level was reduced from 96% to about 25%, but I was pretty fast on the highway. During my stay I was able to recharge the MINI for about 6 hours at 12A/230V, which was sufficient to get the SoC to 86%.

Charging at 12A/230V in the heated garage
On the way back I visited an aunt. I was very relieved that I had chance to plug in MINI E for another two or three hours. So a achieved a full charged battery before driving home on the highway. Due to adverse weather conditions i drove moderately and reached home after 70km with little more than 20% SoC and 30km left.

I've parked the MINI at the return in the open, because on Monday I was not working and the garage was already occupied by the second car of the household.

MINI E 014 in the snow
The next morning the car was completely snowed. The outside temperature was -7°C, were the battery temperature was still at 16°C. After the trip the temperature was at about 35°C.

The following re-charging costs me 20kWh electricity of 20.7 Eurocents/kWh. Extrapolated to 100 km this are about 5.80 €. At the current diesel price of 1.30 €/l this corresponds to a diesel consumption of 4.5 l/100km for financial tie.