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Drew Frye

The same hilarity applies to electric outboards. I love the idea of it, but when I dug into it a few years ago, I ran into the same kW to hp conversion problem, and the same lower speed compromise, as though it somehow excused lower power.

In fact, electric probably is a good answer for some situations. People with small engine-phobia. But tell the TRUTH about hp, not some “equivalent to” myth that is, well, a bald faced lie.

Mitchell Allen

I must agree with you both. I just can’t see the true rationale behind this.
I remember watching a YouTube cruising couple that had installed an electric motor years ago. Only to need a generator to make work! They could barely get out of a marina. Let alone claw off a lee shore.
I was thinking, “wtf are they so proud of?” It just makes no sense in the real world. It ain’t “Green” folks.

Neil McCubbin

We say a green (physically and metaphorically ) boat in the Cape Verde Islands, with a poster extolling it’s virtues on the dock.
While we watched, the skipper was installing a 50kW industrial generator on the coachroof, in prep for his Atlantic crossing.
I asked whether his electric motor could use the 50kW, but he had no idea.
Hard to imagine his batteries could charge at that rate.
I guess he missed my high school science class.

Neil McCubbin

Your headlining the kW to HP conversion is very simple, but understood by too few.
Everyone I went to high schools with was taught that conversation, but I fear that only a minority understood it.
I recently say a promotional video at the Annapolis show for large, expensive catamarans where they boasted that under sail at 7 knots, their prop driven generators produced 340 watts. And that in each hull, no less!
People with me were impressed, until I pointed out that would not keep a 1HP outboard going.
Or that 24 hours sailing and charging would put enough energy in the batteries for about an hour of flat water motoring.
We met Nigel in Sweden when he was doing the field work for his extensive report. Changing propulsion systems frequently to test various electric systems. He was not optimistic at that point in time.

By any rational analysis, pure-electric drive for cruising sailboats is being a Pardey, with a wee bit of power for marina-only manoeuvres. Or for day-sailing where the motor is only to get in and out of port.

Hybrid drives are so unrealistic as to be a scam, preying on the urge to be ecologically good, and the well known advantages of hybrid drive for cars.

Alastair Currie

Not everyone receives a technical education and not everyone that does retains the information. The issue is with the sales pitch as previously mentioned. It’s not even an issue with the products because if there is a consumer demand, the market will supply. I assume most businesses would perform some sort of CBA, even if the outcome is negative but public perception of going green is more important.
Even the way that 1HP = .7457kW can confuse. Is a period a decimal, can the number be confused with 7457kW! Why not use a comma as decimal separator, or even the interpunct (mid dot) that is more common in the UK and countries that adopted UK standards (us Brits use the period in type written decimals, the interpunct in handwritten numbers and fallout with the French who use the comma, but code with the multiplication dot). Not bad for a bunch of people who weigh themselves in stones.
I tend to think of low hp in terms of 60W light bulbs, a common bulb size before LEDs, which makes the scam even more obvious i.e. 1 hp = 12 lightbulbs.
Anyway, this is just a lighthearted observation. Good article and observations on the carefully crafted words of salespeople.