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Showing posts with label snow. Show all posts
Showing posts with label snow. Show all posts

Sunday, January 6, 2013

EV + PV + Snow Can Equal Driving on Grid Power

The snow was just starting to slide off two days after a major storm last year.
After driving the MINI-E for a while it became very clear to me that I wanted to drive electric from that point on. That's really the main reason I'm convinced electric drive will become the preferred powertrain in automobiles; the driving experience is simply better.

I know there are many hurdles to overcome before electric vehicles dominate the roads, but the simple fact that people will prefer them to gas cars once they have the opportunity to experience them, is enough of a driving force to assure they will win in the long run. It will take some time, but eventually electric vehicles will outnumber internal combustion engine vehicles, and by a wide margin.

Once I realized I'd be driving on electric instead of gas, it was an easy decision to install solar electric on my home. I never had the opportunity to make my own fuel when I was driving gas cars, so the prospect of being able to be "fuel independent" was too much for me to pass up and within a year of driving the MINI-E, I had a 8.775kW solar array on my roof. The system generates about 10mWh's per year and powers most of my home and driving needs. I've seen many others do the exact same thing once they get their first electric car, and I'm certain that trend will continue as more and more people get turned on to electric drive.

The next morning after a snowfall
I've had no problems at all in the nearly three years I've had my array and the production has even been slightly higher than my installer predicted. The only thing that bugs me is when it snows I have to wait for the snow to melt off the panels because there is obviously no production with snow covered panels. I really shouldn't complain though because my panels seem to clear off pretty quickly unless it's a very heavy snow fall and the temperatures remain very cold after it snows. My panels seem to be on a good enough angle so that the snow does melt and slide off once it stops snowing and the sun comes out. Others aren't as lucky like a friend of mine Christof Demont-Heinrich, editor of Solar Charged Driving. Christof's panels aren't on quite as much of an angle and the snow seems to sit there for a long time and it really bothers him. He lives in Colorado where they get even more snow that I do in New Jersey, so that only exasperates his woes.

About 20 hours after the snow stopped
About a year ago his frustration over this issue motivated him to do this blog post on the subject. Christof uses a snow rake to clear his panels off but his system isn't as high off the ground as mine is. If I wanted to do the same it would be a difficult and possibly dangerous task so I fall into the "just wait till it melts" category. My roof pitch is 32 degrees while Christof's is only 19 degrees so my snow slides off much easier. Sure I'm still losing some production, and it makes me drive on "dirty grid power" but hey, nobody's perfect!

Two days after snowfall - just about clear
I would suggest discussing this with your solar installer if you live in an area that gets snow before they install the system. Perhaps they can manipulate the racking system so the panels are at a steeper angle allowing the snow to slide off easier, but I'm not sure about that so ask. Of course they would have to make sure that didn't reduce the efficiency of the panels in the first place or you could end up generating less electricity over the course of the year. I'm not an expert on this, but I'm sure your installer can offer some advice on this and it's worth inquiring about. It's not something you really think of when you are ordering the system, but when you look up at your roof in the winter and realize you aren't generating any electric for days at a time, you'll wish you asked and perhaps figured out a way to help alleviate the issue in the first place.
A roof rake can be used to clear the snow if the panels are accessible. My roof is just to high for me to mess with it safely

Wednesday, December 26, 2012

It's sNOw Problem!

I got a call from an ActiveE driver today who had concerns about driving his ActiveE in the snow. Since he got his car last spring he didn't have the chance to drive it in the snow so today would be the first time with a storm bearing down on the Northeast.

His questions were mostly about what to expect as far as range. As my previous post went into detail about, it's really not possible to give someone a definitive answer on it. Will he be stuck in traffic for three hours in the storm? Will the snow be an inch deep or will his car have to push its tires through 6 inches of frozen, range robbing resistance? If you suspect you may have a problem, my advice is don't take a chance - it's just not worth it. These snowy conditions do make an interesting argument for getting the optional range extender on the i3 though. It's there just in case you need it and if nothing else it provides piece of mind in adverse weather conditions.

However with reasonable preparation and not pushing your range limit, driving the ActiveE in the snow is really no problem at all. I've driven mine in a few snowstorms now and here are my suggestions for safe winter ActiveE driving:

First, and this applies to all cars not just electrics, is make sure you have good rubber between you and the road/snow/ice. This is the single most important thing you can do to improve your safety when driving on snow covered roads. Get winter tires if you live in areas where you'll be driving on snow and ice covered roads, they make a huge difference and also make sure they are properly inflated. BMW sells a winter tire for the ActiveE, though I'm not sure what brand it is. The part number is 36-11-2-295-628 and any dealer can get them for you. I also recommend Bridgestone Blizzak LM-25 RFT (run flats), and Nokian Hakka winter tires (excellent in snow but are not run flats). The ActiveE tires are 205/55 R16 and you can expect to pay between $160 and $175 each for a good winter tire.

Use Eco Pro mode when driving in the snow at all times. Eco Pro mode reduces the power to the wheels and while it's not a good thing for drag racing, it is a good thing for driving in the snow and ice. Less torque will keep the tires from slipping and keep the traction control from constantly needing to intervene. 

Use the preconditioning feature whenever possible. This won't help your traction, but it will help extend your range and you may just need those extra 3-5 miles to make it to your driveway one day. It's better to have a warm battery and a fully charged car before you begin your journey rather than have the thermal management system draw from your battery to warm things up.

Keep extension cords in the car, the longer the better. In the winter I keep 150 feet of 12 gauge extension cords in the car at all times. 150 feet is enough to reach the street from most houses. If worse came to worse I would ring a strangers doorbell and ask if I could plug my car in. As embarrassing as that may be, I'd feel worse if I had to also ask for an extension cord. At the very minimum keep a 100 foot extension cord in the trunk just in case. If you find yourself in need of an emergency charge, first try to find a food establishment. They will most likely allow you to plug in and you can at least sit inside in the warmth and grab a bite to eat to kill time. While it wasn't snowing at the time, I had to do this once already and found a Burger King that was happy to allow me to plug in.

I know this should be self evident, but drive slowly! If you don't go too fast you can use the regenerative braking to do most all of your slowing down. I've found the regen to be very effective for driving on snowy roads. The regen slows the car down in a very controlled manner, even better than when using the friction brakes. The traction control and the regenerative braking system seems to communicate well with one another. I've done testing where I drove my ActiveE down a steep, ice covered hill and abruptly pulled my foot off the accelerator so the car would go into full regen in an attempt to try to make the wheels lose traction and skid but they didn't. Instead the car gradually slowed down like it is supposed to and never lost traction. I could feel the traction control working though, as it worked with applying and disengaging the regen to keep the tires from skidding.

It's perfectly safe to charge in the rain or snow
Finally, and I've had people ask me this in the past, yes you can charge the car in the snow. Modern electric cars like the ActiveE are designed to charge in the rain or snow with without any safety concerns. You should obviously use common sense though. If you see a connector is soaking wet or the charging pins in the connector is filled with frozen ice do your best to clean it out and dry it off before you use it. This shouldn't be an issue if the connector head was properly returned to its holder before you used it, but I've seen the connectors laying on the ground in front of charging stations plenty of times. If the connector isn't returned to its proper holster it can be exposed to the elements and you should check it before you plug it into your car.    

So make sure you have good tires, use Eco Pro mode and preconditioning to help extend your range, keep a long extension cord handy just in case and drive slowly. Following these tips you should have no problem driving your ActiveE through the winter in all but the worst storms!

BTW, this is my 100th post on this blog! I'd like to thank everyone who has taken the time to read it and especially those who have commented. Your interest is what keeps me posting! Have a Happy New Year and let's all hope for an electric 2013!