Belt-driven generators

[janice142]

I'm considering a belt driven generator for Seaweed. Is there any wisdom from the field regarding same? The new-to-me diesel does not have an alternator and I'm intrigued by the belt-driven units available. The price is less than half a Honda or Yamaha 2k which appeals to my purse.

2900 watts
http://www.amazon.com/gp/product/B00...g=janice142-20
($400)

or
5500 watts
http://www.amazon.com/gp/product/B00...g=janice142-20
($500)

or for you big guys
10kw generator
http://www.amazon.com/gp/product/B00...g=janice142-20
($900)


Side note: Seaweed carries 275 watts of solar at present (with room for two more 100 watt panels) and I've an Air-Breeze wind gen (latest motherboard) so for the most part I've got power. Not enough to run the reefer full time but with the canning I'll do during the engine swap, really a refrigerator is almost a luxury. Not that I don't like my luxuries!

What's the word from the field regarding the generators shown above? Is this too good to be true?
Charging to a Xantrex TrueCharge20 (it works/knock on teak) but basically I don't have anything AC except the Haier refrigerator and until the battery bank increases (at 450 amp hours currently) I'm not comfortable running the reefer.

Current technology advice sought. Will a belt-driven unit work now? What is wrong with the idea?

[bostonhatteras]

I don't know what engine you want to attach one of these belt driven generators to but you will have a fair expense creating a pulley system and bracketry for it. don't underestimate the load on a set of belts to run one of these. usually gensets have the engine matched with the generator end to put a certain percentage of load on the engine. the idea is that the engine isn't lightly loaded during operation. if youre installing this on a large engine and will run the engine just for the generation of electricity then youll never get an adequate load on the engine and that will lead to problems of its own. too much fuel used for the electricity produced etc. also im sure that belt driven generator needs a certain rpm to operate so your pulleys will have to work to get it in that range.

[Boatsb]

I worked on a 5 kw system. It was a huge alternator hooked to a converter/inverter box made just for that. To make 120v you need e d 1200 rpm. To make all 5000 watts you needed 2000 plus rpms. It would use 15 to 20 hp off the main.

It was a nice idea but not practical. Cant stay on the hook without running a main engine pretty fast.

maybe a trawler could use it while traveling long distances but its not the primary system I would choose.

[Bill Herrin]

I think cruise generators driven directly off the main engine are more common on the left coast where once you leave the marina you're in open ocean much of the time and distances are long so the main engines run at constant speed for long periods of time. Even so the problems of voltage and frequency stabilization can be problematic and as mentioned the logistics of installing a large generator on a small engine can be a challenge. We used to deal with commercial trollers who would solve the logistics with an engine driven jack shaft and use that to drive refrigerant compressors, 110 generators and hydraulic pumps and more so they could live at sea for extended periods of time with only one engine running. Cruisers and sportfisherman going to Mexico often copied these systems back in the 70's and 80,s.

Today I would think it might make more sense to use a dc alternator to charge batteries and a reasonable sized inverter.... I lived and travelled in a highway bus for a long time and used the oil cooled, direct drive 300 amp 24 volt alternator on our 8-71 to power inverters to run 2 roof airs while driving down the road, worked pretty well. If I were looking for a cruise generator system I would look at leece neville 24 volt 160 amp continuous alternators (probably approaching 4 kw usable) and magnum or outback inverter (s). Those same batteries and inverters would also be the anchored quiet generator backup too.

I guess we are no longer in the era of custom solving engineering problems on boats, or at least where the common attitude is if there isn't an off the shelf solution the problem can't be solved (and the boat resold or insured). I'd sure look at the ramifications of doing something 'unusual' mechanically unless I intended to die in the saddle with the boat involved.

[Bill Herrin]

I worked on a 5 kw system. It was a huge alternator hooked to a converter/inverter box made just for that. To make 120v you need e d 1200 rpm. To make all 5000 watts you needed 2000 plus rpms. It would use 15 to 20 hp off the main.

It was a nice idea but not practical. Cant stay on the hook without running a main engine pretty fast.

maybe a trawler could use it while traveling long distances but its not the primary system I would choose.

Scott, I can't recall the name of the company but they were out of the NW.... Seattle? What they did was tie the alternator wide open and get about 60 volts and then they built their own inverter to handle it.... the problems we had with them was the inverter they made was not reliable enough for the intended use.... basically a pita.

Edited to add ,.... Dynamote? Amazing how old minds can't let go of a search for a memory but seldom actually get the memory right !!