Oils4AsphaultOnly wrote: ↑
Thu Dec 03, 2020 11:30 pm
GRA wrote: ↑
Thu Dec 03, 2020 9:42 pm
The proof of concept boat is just that, looking ahead to developing a full-fledged version for cargo use if the numbers work. The example you linked will be using PV to "supply electricity for onboard lighting and equipment", not propulsion. As I stated a few posts back, using PV "for running auxiliary loads is a different matter."
Once again, I'm curious as to how you arrive at the conclusion I'm biased, apparently against PV and battery systems now, despite having designed and/or sold a couple of hundred PV/battery-based systems for off-grid power, including a few systems for sailboats. Personally I'm all for solar car roofs and hoods to run hotel loads, thus saving more of the battery for propulsion.
The power demands of propulsion and auxiliary loads like lighting typically differ by a few orders of magnitude. As with solar-propelled cars it's possible to build solar-propelled ships, provided you don't have to go fast or far, or carry a useful load while doing so.
You're biased against batteries for powertrains. You're hung up about the weight of the battery systems that you've got direct experience with, without realizing that there's more involved in propulsion (both on land and at sea) than just weight alone. You said that "no one is considering using PV/batteries + wind for transoceanic commerce", and I provided proof that someone is. You're biased against batteries as being an essential part of any powertrain, that's why you think that hydrogen will solve the zero-emissions commercial shipping problem first.
Don't forget that the Turanor already navigated around the world on solar+batteries alone (no wind).
You know, if you're going to just make up claims about me with no basis in fact, you should throw in a mention of "Dominion" and "Venezuela" to raise your credibility to that of Trump's legal team; they may be looking for new recruits given Rudi's hospitalization.
I'm not biased against batteries for powertrains, I'm a fan of them when they're the best technology for the job compared to the available alternatives
. Currently, they're well suited for local and intra-regional use with dedicated overnight charging, moderately suited to weekend trip use with no more than 1 enroute QC each way, and poorly suited to long trips requiring multiple enroute QCs, especially in colder temps, where time is a major factor. Again, when compared to the available alternatives.
If/when batteries improve to the point that they're well suited for more transportation uses I'll say so. I expect pigs to fly before transcontinental BEV airliners do, but I'll be happy to be proved wrong.
Nor am I 'hung up' on the weight of battery systems, whether I have direct experience of them or not. It's not just weight, it's also power and energy density, operating temperature range, longevity, TCO, and a host of other factors. I believe in picking the tool to fit the job, not trying to make every job fit the tool.
Re your comment about providing evidence of PV+batteries & wind use for trans-oceanic commerce, have you forgotten that this started with an article about a hybrid wind/H2 fuel cell propulsion system
, and not about using AE to run auxiliary loads? As I said, they're another matter, and both PV/batteries and fuel cells (mostly the latter AFAIA) are starting to be used to replace diesel gensets on ships. It's still small-scale, but as emission regs get tighter we'll see more and more of it.
Mentioning the Turanor has as much relevance to potential commercial development potential for cargo ships as the Solar Impulse has to commercial A/C, or the participants in the Solar Challenge races (held, unsurprisingly, in Australian spring rather than in Canadian or Northern European winter) to commercial trucks. Currently, if you don't care how long you take and don't have to make a dependable schedule, don't care how much you carry, or where you're limited in going by what routes at what time of the year, then solar-propelled vehicles may work. As modern medium and long-range cargo transport does care about all those issues, PV/battery propulsion systems simply can't cope, for now.