I've been lurking on these forums for years now; so much of my idea-seeking brings me here, it's remarkable, even to me, that I've never created an account. Here I am now though, so let's jump in shall we? Background: I'm designing an off-grid house for myself. I have most of the details sorted and have moved on to more elaborate and speculative ideas. One of many is to use the flue gas from my fireplace to supplement a photobioreactor with CO2 and a small amount of heat. Before the flue gas reaches the reactor tank, most of its heat will have already been extracted and put to use, so that is of little concern here. Based on the temperature and design of the combustion chamber, we can assume that the particulate component of the gas is minimal. Based on the size of the photobioreactor, only a small fraction of the flue gas will need to be diverted and compressed. The flue gas will need to be compressed sufficiently to force it through an aerator under a ≈1.5 meter water column. The (greater) fraction of the gas which is not dissolved or consumed by the algae and bacteria in the reactor will be vented outside. Being off-grid, I will have very little energy to bring to bear. However it's done, it will have to be efficient. The Question: What are your suggestions? I was considering a squirrel cage blower, but I doubt it could generate the necessary pressures. A reciprocating compressor would be fairly efficient, but I'm not sure it would have the throughput I want.