Rough calculation to estimate loss of range due to hills?

[rowdyflat]

we live in a hilly part of Australia so many trips involve ascents.

In the future I would like to attempt to drive to Falls creek and down again at the end of the day.

I know  the  battery range  will be affected by the weight of the car and metres of altitude climbed to be added to the horizontal distance when making a calculation of range.

Descending the same hill will regenerate some  of that battery range but there will be losses due to heat and friction.

Does anyone have an idea of the ratio of energy regenerated v energy used ?

[brunohill]

I guess there are a lot of other variables too, like speed,traffic, temperature,dry or wet road etc. One of the EV route planners did include this, you had to add the model of the car you had as well, but I can't remember which one. A couple of weeks ago I went for a drive to the horn of Mount Buffalo. I used 4% of my battery from the bottom to the top and gained 3% coming back down, I got back to Mytleford at the same state of charge that I had at the summit. People don't believe me when I tell them I came down the mountain and did not use the brakes at all. That reminds me of a fellow I used to work with telling me about the broken down Tesla on the side of the road 1/2 way down the mountain. I thought that was strange, what makes you think it was broken down? He said when they were driving up, it had the bonnet up and someone was leaning in doing something, and the Tesla was still there when they came back down again. I told him I suspected a picnic, but I don't think he believed me. You must be careful where you park your EV in the country, because there is a fair chance it will be plastered all over social media as being broken down. I have even had a guy taking pictures when I was trying to have a pee behind a tree once.
 If in doubt, find somewhere in Mount Beauty that you can use a power point if you have to.

[rowdyflat]

so on that basis bruno you figure roughly 75% recovery .
I was thinking somewhere 50-75% assuming a sensible speed ?

[brunohill]

This was probably under perfect conditions:- average speed around 40 km/h, no wind, 19'to 27'C, dry road and the new low rolling resistance E-primacy tyres.
Although I do admit to planting it a couple of times, going up, on some very steep sections just to confuse the XR8 falcon that was sitting on my tail.
I found it interesting how so many big fuel guzzlers were joy riding up the mountain when nobody can afford petrol or diesel due to the fuel shortages and price rises. I have a idea, as there are fuel shortages and we have basically no reserves, lets reduce taxes on it to encourage more use and introduce new taxes on EVs. 

[rowdyflat]

ICE cars use large amounts of extra fuel going up the mountain and not much regeneration coming down but no one notices the petrol gauge and you can always go to the service station .
Scummo doesnt want to ruin the weekend so they reduce fuel excise and will be ALP 's problem.
I wonder if the Vic govt will reduce our EV tax by 50%?

[johnmath]

I think the "round cycle" regeneration efficiency of our Leaf 2016 is somewhere between 50 and 75%, probably closer to 50%. That's why it is fun to drive with a 'hypermile' technique, which basically means avoiding using regernative braking (or any kind of braking!) When we first got our car 4 years ago I did some trip logs and about 25% of the energy used was from regeneration. Compare that to an ICE which uses a lot of petrol going downhill as well as going uphill! In fact ICEs are so inefficient that driving with extra load or into a head wind barely affects consumption, because nearly 90% of energy usage in and ICE is just turning the motor over along with all of the ancillary pumps needed so it can work. Adding a bit extra load to pull a trailer for example doesn't make a lot of difference to consumption when so much energy is being burned just keeping the pistons pumping.