Teslas Rely on Efficiency
Our Teslas have some very impressive efficiency numbers as explained in this InsideEVs report , their success depends on it, we wouldn’t be buying as many if they didn’t perform as well as they do. Many of us rely on those operating efficiencies to justify purchasing a Tesla instead of a less expensive gas equivalent. During the summer we see those same advertised low energy consumptions and long range numbers that impressed us when we bought the car, but now it’s getting cooler and we start using the cars heating system. We also notice dots appearing on our energy bar and regenerative braking isn’t working as well.
During the summer we don’t have to think about our battery charge very much, if we forget to plug it in or we have an extra stop it’s generally not a problem, but not during the winter. During the winter we watch that battery display and range indication like a hawk. We carefully manage trips to ensure that we have enough battery capacity with a comfortable safety margin. In an effort to reduce energy consumption we sometimes compromise comfort by doing things like dressing warmly in the car so we can keep the heat turned down or using the seat heaters instead of the cabin heat. A noble sacrifice in the interest of being environmentally responsible, but EV revolutions are a whole lot easier when you don’t need to ask people to make those sacrifices.
Tesla efficiency has primarily been a result of their technological advancements, but practical engineering also goes a long way, such as the use of lighter materials and fewer parts. The new Tesla Octovalve and heat pump combination is an important example of a technological advancement that will improve cold weather efficiency, but as Musk has pointed out, the most efficient part is the part that you don’t need. If we use that same principle in keeping our cars warm, is it better to efficiently produce heat or simply reduce the amount of heat that we need to produce?
Insulation certainly isn’t a new idea, people have been wearing fur coats for a very long time. Our homes have been the primary beneficiary of insulation and we have become very good at heating them very efficiently. Of course, heating our homes efficiently is all about reducing the monthly energy bill, we rarely worry about actually running out of energy to heat them. Now imagine your home being powered by a battery instead of a limitless utility, efficient heating takes on a whole new perspective. Now we are less worried about the energy bill than we are about the energy supply.
The concept of insulation certainly isn’t rocket science, we’re creating a thermal barrier to keep the heat where we want it. Coincidentally, our batteries like to be roughly the same temperature that we like to be. That’s the temperature range where we are comfortable and perform the most efficiently. We don’t spend a lot of time thinking about the insulation built into our homes but go try living in an old farm house and you will quickly develop an appreciation for modern insulation. Our old internal combustion engine (ICE) cars have so much waste heat that it was like having a blast furnace in your home – you could literally drive around with the windows rolled down and still have enough heat left over to be comfortable. Very wasteful and very inefficient.
Learning to manage the temperature of our battery and cabin effectively and efficiently is not a difficult process, it just takes a little knowledge and effort. As we get better at it we will gain the same benefits of comfort and lower cost that we achieved by insulating our homes.