Well, keeping the battery warm is one goal among many, it’s not something everyone needs to worry about every day.
And I’m not sure a big metal battery in/under the car is going to stay warm all night because the roof is painted black.
but really, cold weather and electric cars just isn’t a good mix.
There’s problems. Rapid refueling infrastructure for NG has to be built out. A NG tank takes an inordinate amount of space in the vehicle. NG is still more suited to commercial use which can depend on a small number of fixed refueling locations, and a pressure tank in a larger vehicle like a truck stills leaves you with an acceptable amount of cargo space. Honda has sold a NG car for several years - you still only find them in limited markets where NG filling stations are available, and the tank takes an appreciable chunk of the trunk space - I just looked up the specs out of curiosity - the Civic NG model has 6.1 cu ft of cargo space, while a base Civic sedan has 12.5.
ETA:
Honda also sells an appliance for refueling these cars overnight at home from your residential gas line. It has an electric compressor on it to fill the high pressure tank from the low pressure residential line. I wonder about the practicality and of doing that, too. As well as the ramifications if an appreciable number of customers started doing it.
The gas turbines at power plants are vastly more efficient than an internal combustion engine. Even with some transmission losses and having to lug the batteries around, electric still wins out efficiency-wise.
Unfortunately, people are going to attach a surprising amount of importance to the car’s color, and white has been the most popular color for some time. Way back when Henry Ford painted all the Model Ts black because black paint dried quicker and made his assembly line more efficient, a lot of people were willing to pay some aftermarket business to paint them some other color.
And the wires coming from the power plant might be more efficient than pipelines, too. You always have inefficiencies of producing and transporting power.
Electric cars are also more flexible in terms of infrastructure. Most alternate fuels have a chicken-and-egg problem: There’s little incentive to build fueling stations if there are few cars that use the fuel, and there’s little incentive to buy cars that use the fuel if there are few fueling stations for it. Electric cars have that problem, too, starting out, but once the electric recharging infrastructure is in place, it’s a one-step process to change the underlying fuels: You just need to build new power plants, and the existing cars won’t care.
Followup on cold weather: once you get going, does the battery generate enough internal waste heat to operate itself?
I suppose that depends in part on the geometry of the battery array?
[Nitpick]
I’m guessing that whoever made that graphic meant to pen kW instead of kWh under the “Cheaper Batteries” heading.[/Nitpick]
$485 per kWh is an exorbitant cost for that amount of energy.
There are natural gas vehicles in other countries (and some buses in the USA). I wonder why we don’t see more of them here… maybe the infrastructural difficulties of building a new distribution network vs electricity, which can usually just be modified at the site itself?
According to Wikipedia, compressed and liquified NG can be 4x to 20x more energy-dense than lithium-ion batteries… hmm.
Usually, the engineering challenge is to keep the batteries cool while they are being used (i.e. providing power). The Nissan Leaf has air-cooled batteries, with a fan to provide the airflow. Tesla uses liquid-cooled batteries. Presumably, these cooling mechanisms don’t kick in unless the battery temperature reaches a certain threshold.
This is not very different from gasoline engines, which are inefficient when cold, but get hot very quickly and need to be actively cooled after that point.
Not quite. They had but pulled the plug a few years ago. The appliance is now, after a two year hiatus, for saleagain but not from Honda.
A few public fast fill stations exist (currently 618 across the United States) but filling quickly heats the gas up, expanding it, allowing a less complete fill. Most of the infrastructure is private built for and used by fleets and fill slowly overnight.
So, for a given car+passenger weight, does an electric car generate the same amount of waste heat as a gasoline engine?
I had imagined them running cooler, but I guess that’s not necessarily true.
I’d guess that that’s the cost for 1 kWh of battery storage for a single charge.
No they do not generate that much heat. Which leads to a problem in the winter … an ICE vehicle uses that “waste heat” to provide interior heating and defrosting; an EV has to use electric power to provide the heat (and in some cases then exhausts the interior air past the battery to help keep it warm. My plug-in hybrid has a much smaller all EV range in winter than in summer.
The Wikipedia page Electric Vehicle Battery uses cost per kWh.
I figured as much. Could you guestimate the temperature-to-efficiency drop? How cold to lose 50% of your range? 32F? 0F?
Utilities are taking advantage of the current glut in natural gas production. Fracking has dropped prices to the point that producers would prefer to back off, but they purchased leases under old prices that require them to produce or lose the lease, so they are trying to make up for low market price by increasing volume, driving price yet lower.
It is unsustainable in the long view. Electrical producers are going to have issues when gas prices rise as they eventually must.
Ha - you pulled a fast one there. Some gas turbines (especially aero derivatives) are less efficient than internal combustion engines (diesel engines). But overall, your statement is correct that power plants running on combined cycle are far more efficient than a gasoline engine.
Well diesel wins efficiency wise also - but last I checked majority of the cars are gasoline powered. Efficiency is not the only criteria, car drivers care about - its also ease, cost of the car, refueling intervals, maintenance schedule, …etc. etc.
The biggest question in this debate, long term, is the price of natural gas and the quantity that will be available. There are these options :
1> Natural gas powered cars. Cons - Need mass infrastructure change, frequent refueling, less efficient, less boot space, … Pros - Car price does not go up, Folks spend less on fuel, …
2> Electric powered cars. Cons - High Price of car, needs (less intensive) infrastructure change, limited drive time, refueling takes long time, less boot space too … Pros - Folks spend less on fuel, Overall efficiency high, …
3> Convert Natural gas to Gasoline. Cons - Need new plants, may increase price of gas (?) … Pros - No change of current cars or infrastructure
Again the above is from the US perspective.
Producing power from natural gas at a power plant (into electric power, transmitting it, storing it, and converting it into motive power) is much more efficient than producing energy for motive power in the vehicle. As Forbes put it:
Another issue is that while NG is plentiful in North America right now, no one knows how many decades it will last. An infrastructure of vehicles and fueling stations built for CNG vehicles may be dealing with rapidly rising prices if and when NG supplies tighten again. OTOH if NG supplies tighten and prices rise electricity can be generated by other sources. Using electricity is by its nature a diversified energy source which can be switched to other, more renewable sources, if and when those sources out compete NG on price.
The one con to EVs is range, which for now is offset by using a plug-in hybrid that provides most daily commuting on grid-derived power with a battery just big enough for that but which is capable of using gasoline for extended range driving.
[quote=aNewLeaf]
In my car (Ford C-Max Energi) I get 24 miles usually of all-electric in summer, down to 18 or 19 as the temps go to 40 and below, and below that it would depend on my use of heat and defrost. I tend to just use the seat heater and the defrost as needed which probably gets me down to 16, but if I am driving with my family and have the whole car heat on and toasty probably to 32 will get me down to 12 or less. Not even because the car turns on the engine as soon as I turn on the defroster no matter what. What I’ll do in winter if I am driving more than a short trip is start in regular hybrid mode (I can select) and get the car warm with that and then switch to EV when everything is warm and defrosted. If I was planning better I could preprogram the car to warm up the cabin while it is plugged in but I have been too lazy to do that.
Several friends who have Prius hybrids have noted that their mileage is noticably worse in winter – like 25-50% worse. Some of this is due to unavoidable winter issues – stiffer transmission, flatter tires, less dense gasoline – but a lot is due to the hybrid design. The Prius gas engine normally turns off and it runs only on batteries when possible, but it is programmed to not turn the gas engine off in what Toyoto considers very cold temperatures.
Here in Minnesota, we may never get above that temperature for a whole month during mid-winter! So in cold climates, much of the efficiency of a hybrid vehicle is lost during winter season. Though most are still pretty efficient overall.