What you can do with a mountain and a battery

[valkraider]

Starting at Timberline ski area

 

 

Government camp at the bottom of Timberline Rd

 

At the point where I stop coasting:

[C-MaxSea]

And with "14" miles left in the battery, were you able to hit 30 miles @ 999?  Hope so, very cool!  Nick

[MikeB]

That's just spectacular, Valk. I managed to add about 3 miles to my batt after getting down to hybrid mode, but you've gone way beyond me. Well done.

[valkraider]

That's as far as I can coast on that route. But it is awesome going skiing and being able to recover some of the energy that was spent driving up the hill. :)

 

Also, not touching the brakes at all on my descent is AWESOME, and saves me tons of stress and brake pads. Grade Assist worked flawlessly!

[MikeB]

I reall a story about Pike's Peak, on the way down there's a mandatory stop, and the park rangers check your brakes with an infrared thermometer. Obviously, most cars have serious problems with overheating brakes, which can lead to failure, so this is a very reasonble precaution. Of course, someone came down the hill in a plugin of some sort (I don't recall which one), and their brakes were perfeclty cool. They got measured repeatedly, and the rangers were certain their thermometers had broken. I gotta say I love the ability to capture that energy rather than wasting it.

[asb]

Very impressive.  Makes me jealous that I live in Flatland Florida and do not have an Energi.

[valkraider]

It was a Volt:

 

http://m.green.autoblog.com/2010/08/18/chevrolet-volt-continues-to-handle-pikes-peak-with-ease-w-vide/

 

Capturing the downhill energy is one of the main reasons I wanted an Energi. Not even a normal hybrid car can do it as their batteries fill up before the bottom. :)

[plus 3 golfer]

Interesting, do you know what the elevation change was?  Just looking at a topo map, it looks like maybe 4200 feet (5800 - 1600) at about 16 miles.  That's a lot of potential energy - 4200 pounds at 4200 feet =  6.6 kWh.  There would be drag losses, perhaps friction braking, and energy conversion losses as one descends.

 

It looks like the charge level at the end of the 16 miles is slightly higher than at the beginning. So, if that's the case you traveled 16 miles "free" and stored some of the potential energy.  It also looks like after 5 miles, you used some of the initial stored battery energy and later built that energy back up and even slightly more than the initial level.   It would be interesting to see what ones FE would be in a gas only similar vehicle and also what the fuel economy of a regular C-Max hybrid would be over the same downhill route.  It would also be interesting to see the overall FE over 32 miles for the vehicles (uphill and back down).

 

Very impressive.  Makes me jealous that I live in Flatland Florida and do not have an Energi.

No, you're better on flat land.  Remember it takes energy to climb 4200 feet and there are losses in converting energy from rotational to electrical and back to rotational. So, overall you are better off traveling 32 miles on flat land than 16 miles up and 16 miles down whether in a hybrid or an energi. :)  Most won't have 4200' elevation changes and thus won't have such potential energy to capture / use.  The economic benefit of the plugins for most is "filling up" with a cheaper energy source (electricity vs gas).

[valkraider]

According to Google Earth, from the exact point I parked was 5869ft and the exact point I stopped was 1479ft.

 

That is direct - I was "nose out" in the parking spot right into the road and coasted to a stop on the side of the highway as best I could without impeding traffic.

 

There would be a smidge lost due to one stop sign and accelerating back to 45mph, and there are a couple teeny uphills where I touched the accelerator to keep at 45mph so as to not impede traffic.

[valkraider]

It looks like the charge level at the end of the 16 miles is slightly higher than at the beginning. So, if that's the case you traveled 16 miles "free" and stored some of the potential energy. It also looks like after 5 miles, you used some of the initial stored battery energy and later built that energy back up and even slightly more than the initial level.

No, the battery level appearance is misleading.

 

The battery display starts over when you fill the "small hybrid only battery". It goes back to the bottom and you start filling the "big Energi battery".

 

Since the display doesn't allow us to see actual percentages, based on rough eyeball estimates of the battery gauge I filled about .6 or .7 Kw in the "small hybrid battery" and then another 3Kw in the "big Energi battery". Maybe at best 4Kw total? I wish we had a display which would show us the Kw gained from regeneration.

[plus 3 golfer]

No, the battery level appearance is misleading.

 

The battery display starts over when you fill the "small hybrid only battery". It goes back to the bottom and you start filling the "big Energi battery".

 

Since the display doesn't allow us to see actual percentages, based on rough eyeball estimates of the battery gauge I filled about .6 or .7 Kw in the "small hybrid battery" and then another 3Kw in the "big Energi battery". Maybe at best 4Kw total? I wish we had a display which would show us the Kw gained from regeneration.

So, there are two battery displays. I wondered about since the battery pics are different.   It certainly would be nice to have a % remaining displayed.   And, I thought you should have captured a significant amount of the potential energy instead of my interpretation of the battery pics.  4 kWh seems very reasonable out of 6.6 kWh given that the difference then is mostly drag and conversion losses over the 16 miles.  So, yes the energi storage capability is a significant benefit going down long hills over the hybrid.