I'm a new member to the forum having just completed an introductory post. I'm interested is putting together a sustainable aquaponics system utilizing a BSF composter as one of the elements.

Living 16 miles inland from the Oregon Coast, we have fairly mild summers and winters, although the temperature does dip below freezing for a week or two at a time. The big question in my mind is not necessarily directed to this forum, although I am interested in opinions. The big question is: can I raise warm water Tilapia and high value vegetables in a greenhouse in Oregon in the winter and make a profit?

For this forum, I have a question concerning heat transfer in a BSF composter. I've read that some folks are seeing a 10 degree (F) temperature rise in their BSF composters. Has anyone ever measured the heat produced by the composter? Ideally, I'd like to know BTUs per thousand BSFL, or BTUs per pound of BSFL. Something along those lines.

If nobody has the information, then I can make the measurement once I get my BSF composter set up and running.

Bob
http://theoldstrawberryfarm.com/
Practicing sustainable insanity

See this post (link) for some temperature info.

Thank you!
After following the fan-out to several other links, I came across this report on composting: http://www.builditsolar.com/Projects/Sunspace/NewAlchemycompost.pdf -- much of what is said can be adapted to BSF with BSF possibly giving better results based on the higher metabolic rate of BSF. This should be true for greenhouse area costs, CO2 production, and heat production,

The report mentions 1530 BTU/lb of manure and 0.29 lbs of CO2 per pound of manure. So, now all I need are similar numbers for BSF.

BTW, at this point I'm an armchair BSFer. The corn is in the pot fermenting and the composter is on order.
Bob

A couple of years ago, I bought some wireless temp monitors that featured both a probe for inserting into the substrate and a probe for monitoring air temp inside the bins. Seems to me the probe units were like 25 bucks a piece and the receiving station was maybe another 30 bucks. The cool thing was, it would automatically upload to an internet site via a link to your home computer and track both probe readouts online on an Excel spreadsheet which allowed graphical analysis. I'll see if I can find the name of the units and post a link. (Wish me luck because that was two laptops ago!)

Regarding your per 1000 or per pound calculations, here is some data I use (after laboriously counting and weighing mature BSF larvae) which may help count or weight computations (it shows count of mature BSF per unit of weight)

5556/kg
158/oz
2525/lb

Your assumption that the heat generated in a bin is attributable to population or weight of BSF may be flawed, however. I believe much, if not most, of the heat is a result of microbial activity operating in the substrate (similar to what happens when compost heats up). You might want to factor that into your research! Keep us posted with your results!

Brian thanks for this. I was looking for data like this a while back and couldn't find a link (similar to your 'two laptops ago' situation)

[quote="BorealWormer"]

At one point I had volumetric data too BW, but the location of that info also escapes me at the moment. I'll see if I can find it.

Mature larval weight may vary according to diet and climactic conditions. My weighing and counting lead me to conclude that the larvae in MY system weighed 0.018 grams per larva. That may not hold true for all systems.