In colder climes we have block heaters and even in-line heaters and coolant circulating pumps to keep engines warmer than if those devices weren't there. We also have battery warmers to keep your friendly electrons from freezing solid in winter (OK, electrons don't really do that, of course, but you get my drift). For many years, while living and working right up by the Yukon border, I used both types of devices installed in many types of previous vehicles, and was very glad I did. My experience says this: if at -45C your garage circuit breaker fails, you don't know about it, and overnight in frigid temperatures your block heater doesn't do the job it was designed to do, the morning startup either doesn't happen or, if your poor car / truck does actually start, the consequences are pure torture. Bad, bad stuff.
Anyway, right now it's Summer -- and what am I doing thinking about block heaters? It's because I have to replace the 110V plugin wire for the block heater on our silver V70R manual -- the plastic cabling was damaged some time ago, and will short out if plugged in.
So, this got me to thinking.
Although I don't remember exactly where, I recall reading -- probably more than 15 years ago -- an article about "new Volvo technology". This was "new" back then, of course. The article was about "eutectic salts" that were being experimentally tested and evaluated as a heat storage & recycling medium. The system was designed to be used as follows: the engine would be brought up to operating temperature, heat would be extracted from the circulating fluids (coolant + oil) and then transferred into a eutectic salt that stored that heat in an insulated container.
Then, overnight (especially in cold climates where this would be particularly useful -- duh!), the engine would begin to cool off. However, the heat stored in the eutectic salts could be "tapped". So, this heat could be used in the equivalent of a "slow burn" process -- with a thermostat and pump, the oil and coolant would be periodically circulated through the insulated eutectic salt reservoir (or vice versa depending on which moving parts would suffer the least wear -- I don't remember which way it went). Without the need for electricity (except for the circulating pump which could be powered with a mini Sterling engine from the same stored heat), this process would keep the engine warmer than it would have been if it was simply permitted to sit overnight and potentially freeze solid.
And as suggested above, in really cold, deep-freeze conditions, this could actually make a lot of sense. So, engine startup would (at least in theory) not be as thermally stressful as it would in "normal" conditions.
Very interesting. I don't remember any findings about how often you could "cycle" the salts this way, or if it was essentially infinite.
Could be that back when this was "new" in Volvoland (and no doubt in other realms, too), the costs for such a system weren't justified -- so, we never saw anything beyond experiments with the engineering. But, things have changed. Has anyone out there on the forum seen anything about his "green" technology lately?
Cheers / Blueleezard
