Replies

1. Expert Member
   Dana Dorsett | Oct 23, 2020 04:32pm | #1

   I'm not sure, but I wouldn't be surprised if they're trying to expand some of the concepts they used in the development of the heat pump they designed for the Model Y, which is explained only minimally here:

   https://www.tesmanian.com/blogs/tesmanian-blog/deep-looks-into-tesla-model-y-s-octovalve

   or...

   https://jalopnik.com/the-tesla-model-ys-octovalve-and-cooling-system-manifol-1843342722
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   "In the case of the Tesla Model Y, instead of having an air-to-refrigerant heat exchanger (condenser) at the front of the car, there’s instead an air-to-glycol-based-coolant low temperature radiator out front. That radiator sends cold coolant to the “stack" -style condenser, which chills the gaseous refrigerant to bring it to a liquid state.

   But this condenser isn’t just used to replicate what a typical car’s condenser does in an AC system. It also acts as a key part of a heat pump, which is a way to heat the cabin efficiently without relying entirely upon an electric heating element. A heat pump can be thought of as an AC system in reverse — strategically using the compressor and an expansion valve to heat refrigerant, and using that heated refrigerant to warm the cabin or possibly other components.

   This system is very complex, even Musk does not know the way how to easily explain it. The main thing is that Tesla has all of this stuff tightly integrated into a small package, and controlled with complex valving. "
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   A multi-zoned system using metered amounts of glycol solution rather than refrigerant to the remote heat/coolth emitters limits the total volume of refrigerant needed, but is a common enough approach used in hydronic output ground source heat pumps for distributing both heating and cooling. It's not clear what Tesla's "special sauce" would be for a home sized heat pump system (other than cheaper cleverer more compact valving), not that the current state of the art for cold climate compressors doesn't have plenty of room for improvement- it's nowhere near the theoretical limits for the types of refrigerants in common use (such as R410a , HFO1234yf, ammonia, or propane.)

   It would be nice if whatever they came up with uses less impactful refrigerants than HFCs (all of which have extreme global warming issues), and less expensive refrigerants than the HFO1234** variants. I haven't figured out which refrigerant(s) is(are) used in the Model Y's heat pump system. Many automotive AC systems designed for HFO1234yf will work just about as well using cheaper (but far more climate damaging) HFC134a, and it's still legal to use the latter in the US (but not Yurp.)

2. Expert Member
   BILL WICHERS | Oct 23, 2020 06:20pm | #2

   Solar still works electrically even if you have a gas furnace -- it's not an "all or nothing" kind of deal.

   While I like the Tesla products (except for the truck, not sure what they were thinking with that one), and they are currently opening a new dealer only a few miles from me, I don't think I'd say they are "transforming the auto industry". What they are doing is serving a niche for relatively high-end electric vehicles. The "regular" auto industry is taking care of the mass market, and reasonably well albeit a bit slower than I'd like to see.

   I will be interested to see what their heat pump can do, but I'm not sure there is any huge leap forward to be made there in comparison to what is currently available. As Dana mentioned, transitioning to newer refrigerants is probably about the biggest "green" improvement that could be made in that market.

   Bill

1. Expert Member
   Dana Dorsett | Oct 23, 2020 07:15pm | #3

   >"Solar still works electrically even if you have a gas furnace -- it's not an "all or nothing" kind of deal."

   That's absolutely true, and a good point.

   I think you're under-rating the impact Tesla has had on the auto industry. By starting out with luxury stuff as their first move they forced the hand of other vendors to get in the game or be crushed. By opening up many of their patents to public use they jump-started (as it were :-) ) the electric car industry in the rest of the world too, making it possible for the "me too" lower cost vendors to deliver higher quality options.

   Most of the lower priced EV vendors aren't currently in the North American market, but some will make inroads in the next handful of years. BYD was planning to build a plant in Mexico to serve the North American market prior to the trade wars and the blunting of US environmental standards. Those plans got put off, but they won't be put off forever.

   Nissan wasn't really making a big splash with the lower-key Leaf (even though it's a pretty good car in most climates), without the big splash of Tesla I expect the transition to EVs would still be languishing in Europe. Albeit small compared to the North American or Chinese market Norway now sells more EVs than internal combustion or hybrid electric markets.

   https://cleantechnica.com/2020/07/09/69-of-autos-sold-in-norway-in-2020-have-a-plug/#:~:text=Norway%20continues%20to%20be%20a,auto%20sales%2C%20another%20global%20record.

   (Dark red in those charts indicates full-EV, lighter red is plug-in hybrid.)

   I doubt that would have happened this quickly without the existence, innovation, and market presence of Tesla. They were able to prove that EVs are cool enough that real (if primarily wealthy) people would buy them. Starting at more modestly priced part of the market (the way Nissan did) didn't have the same appeal- very few were out trying to eat Nissan's lunch on the runaway success of the Leaf. But when Tesla became hands-down the biggest selling luxury car the rest of the industry took notice- they HAD to, since Tesla was (and to some extent still is) eating THEIR lunch!

   Right now some of the big car companies are facing the potential "Osborne effect" , where anticipation of their EV releases cutting into their internal combustion car sales. This is looking to become VERY serious over the next few years. New car sales are falling- people are starting to get that EVs are better than what's currently being sold, and that in a handful of years will be cheaper than internal combustion engine cars. In the short term it means more business for repair shops keeping the already-sold cars running as people wait for EVs to become more affordable.

   The price/performance of lithium ion batteries is getting better every month, and the day when EVs break through the price barrier keeps moving up with those incremental improvements in economics. Some of today's bigger car companies are unlikely to beat the Osborne effect and will go the way of Osborne Computer well before 2030.

1. Expert Member
   BILL WICHERS | Oct 23, 2020 08:23pm | #4

   Actually Dana, I would argue that Tesla's biggest impact on the auto industry wasn't that EV's are "cool enough", it was that they showed that EV's could be high-performance. People were really surprised with the 0-60 numbers Tesla could achieve with their early models. Many people thought EV's were just glorified golf carts and sluggish performers, which I think would have been a big perceived negative until Tesla came along. At the time, there were few other EVs out there, and those that were (primarily the Volt I think), were targeted at fuel economy and compact markets. Tesla came along and showed full-size sedans with high performance and all-electric propulsion, and they made a big splash and got noticed. I think that was by far their biggest contribution to the industry -- changing the perception of the general public that EVs can perform as well, or better than, conventional vehicles.

   Europe I think is a very different market in that their cities tend to be much more compact than ours in North America. EVs make huge sense for them, even those with limited range, since their average commutes are likely to be less. In North America, range is a bigger issue. This was a huge design goal for the Volt, and Tesla also helped with that -- their early models had ranges comparable to a full tank of gas on a regular car.

   Since I live in the Detroit area, and it's pretty much impossible to not be in some way connected to the auto industry (the plant where my current project is does the heat treating for most of Chrysler's gears, for example, among many other kinds of bearings for others), I've seen a lot of new battery R+D firms and other propulsion technologies. There is a lot of talk about that kind of thing, and both GM and Ford are heavily involved with making their REGULAR vehicles all-electric in the near future. It's happening faster than I think many people realize, and a big goal for them is to keep the price point comparable to put the new EVs within reach of families that would otherwise be purchasing typical mid-range vehicles. We're likely to see many more EV options out there in the next few years.

   It's worth keeping a pair of spare slots free in your circuit breaker panel for a future EV charger :-) I imaging the readers of GBA are likely to be early adopters of many of these new vehicles. I bought my Volt at the end of 2011, for example. It still works fine, and it still has essentially the same electric range as when new. Battery degradation with age has turned out to be much less than the designers had originally anticipated, which is a good thing.

   Bill