The Ivan labs circulators traditionally incorporate a March magnetic coupled head. These things are about bomb proof as it gets for all kinds of tasks. They come in stainless or brass and are suitable for fluids at 250°f operating temps.
http://shop.solardirect.com/advanced_search_result.php?keywords=ivan+labs&osCsid=v8dmhnp918avf3kdbdho8anhd6&x=9&y=7
A 3w El CID would do the 2gpm. 16 inches max head though and at a much lower rate.
I use a 20w model to drive our woodfired dhw boiler. Its storage and delivery are a poly barrel with an immersed coil hx for potable water and open (atmosphere) tank, like a fountain containing the boiler fluid, purified water.
We have installed and used these circulators ourselves for 16 years, great off grid gear.
People in Scandinavian countries have adopted TEGs and dc circulators for wood fired boiler circulation for a couple decades now. The byproduct is sometimes
energy for lighting. They are operated with outdoor mounted radiators, generally.
What pump are you indicating? Looks interesting if it can take the heat. Is it positive displacement? That is high head for 13w-14w by any other means i know of.
We ran a vane type pump and a diaphram pump (both polymer) at 150°F for a season without issue, but i think time would have killed them both sooner than a permanent installation would require.
~
'Old tricks are the best tricks' Alcohol, methane, wood, plant and animal oils. Renewable biofuels.
I remember a
video of a guy running a chainsaw with a woodgas generator made from a 5 gallon tar
bucket, some tube and a
coffee can or two. Cant remeber the blower, probably a small diameter woodstove blower. It ran, no lubrication though, so just a demo.
At one time we had 2 VW
Rabbits and 6 engines,
milk crates of fuel distributors, etc.
I wasnt keen on driving the little things and wanted a grid tied SVO generator sized to heat our house and dhw...ahh,
city slickers we were!
Wheeling back around to the topic; wood-gas, heating, electricity.
Wood-gas engines are appealing from a practical standpoint...wood-gas has a minimum fuel refinery apparatus and can be produced for use on demand or stored.
Wood fired stoves and heaters run on wood-gas and are way more simple than most wood gassifiers designed for fuel production, both in the processing of feedstock and during operation.
Have not seen an engine yet, that i adore for being clean, quiet and vibration free. In a past mode of operations, yes but i like it quiet and ungreasy nowadays and without trips to hopefully properly dispose of gick.
I could consider the Sterling. They can be fabricated entirely or use some existing machinery modified to a new duty. Having a pure fabrication can help ensure parts are always available and repair knowledge is nearby.
TEG module chips, by comparison are manufactured by pretty esoteric processes to get high power density.
Youtube has plenty of Stirling exibits i didnt realize there were so many nowadays.
This looks nice, expensive and capable. I like it if it will operate lubricated with animal or plant oils and be isolated from being a general nuisance around the homestead.
http://diystirlingengine.com/sv-2-stirling-engine-generator/
Not so capable (.10 amp at 12v) way doable though.
http://www.scraptopower.co.uk/can-stirling/build-a-stirling-generator
Did find this while fishing around. It allows use of high efficiency, insulated fireboxes.
There are modules that operate at low temp, 325f-ish also.
http://tegpower.ca/product/wood-stove-thermoelctric-generator-rabbit-ear/
I have seen TEG modules up to 400w for around $100. The rest of the generator and heat sink would need to be diy, its just the power circuit.
I get all twinkly eyed at the thought of incorporating a solid state brick to throw on our stovetop. An iron box that converts woodgas to heat and an aluminum box that converts incident heat to electricity with only the sound of the fire being heard, no oil to change, no whirligigs, just long service life, easy component replacement. A fire box, electrical box, a circ pump, and snap disc temp switch.
Branches and cord-wood ( or other biomass) in, heat and electricity out with a minimum of Rube Goldberg-ness, which engines always remind me of. Too many knuters and widgetry.
The radiators commonly used for Scandinavian installs i have seen are extruded aluminum, pretty beefy like parallel manifold pv rail full of fluid, and not a common liquid to air heat exchanger with fine fins on the waterways. A radiator like this
should last a lifetime if kept from experiencing acidic antifreeze for a prolonged period stainless flex line and associated brass fittings should also last a lifetime or more.
It is quite likely that you would need to replace most steel constructed wood heaters before the TEG and i have seen plenty of 20 plus year old
solar thermal circulators doing their jobs happily, but also replaced some that were only in service for 15 years or so.
Antifreeze (propylene based), 5 years, but i have also seen report of 30 year old antifreeze operating in a 12 collector solar thermal application.
Not sure of the temperatures experienced by the transfer fluid in the Devilwatt or others and there is no reason to limit prospects to liquid cooling air is fine, just more bulky and... fans all over the stove kinda kill it for me, if they are located in occupied space. Havnt heard an aircooled one operating though either, it might not be that noisy.
Great cogen devices for a dependable kWh or two as a byproduct of woodfired space heating or process heat, especially in combination with other renewable energy sources, at least at sites like ours. We get long strings of overcast days that coincide with a heating requirement.
We generally use 1-1.5 kWh daily, somedays as little as .4kwh and some days as high as 3 kWh and heat with wood 6 months of the year, so a TEG makes sense, even a 50w.
One of our pv arrays is 1100w on an outback mx60. This array produces 100-400 watt-hours on overcast days which can last 15-20 consecutive days, sometimes nothing at all for a few days in that period. This will likely happen in november, december or january somewhere. It forced us to use a laundromat a couple times as a precaution to battery longevity. Dollar for dollar, a 100w TEG would have been 2-4 times as effective as another 1100w pv array, mounts and wiring during a period like that.
Not having clothes contaminated with commercial laundry detergent and fabric softener residues from the previous persons laundry.... priceless!