Maybe I have too much time on my hands (not really...), but here's a challenge... We have a good sized room (12x20) that experiences a lot of heat gain during the day. 80 square feet of south facing glass plus two skylights. I'm going to cover the glass with 90% sunblock screen material, which should cut down on some of the solar gain during the summer. We also have an LCD tv and av receiver that generate some heat. I've thought about relocating the receiver, but that's challenging. The two windows in the room are too narrow for conventional AC units. We run a large AC at the opposite end of the house, the closest location where I can mount a window unit. For now, we're making do with the window AC units. At some point we'll invest in mini splits or perhaps a high velocity system...but that's a ways off. The room has an HRV return feeding fresh air in. Typically that air is just a couple of degrees higher or lower than ambient inside air. The HRV unit is in the basement, directly below the room in question, with easy access to the ducting. So I'm thinking (which usually gets me in trouble...) Can I cool the air being returned by the HRV? One approach is to insert a cooling box inline that has a small water radiator and use either my well water supply or a ground loop with a solar powered pump to provide the cooling function. I have not done any testing of ground or well water temperature yet. The ground loop would be easier, as I would not have to deal with circulating house water through this setup. I don't know if this would provide sufficient cooling to be worth it. I've done some googling and found people creating McGyver type cooling systems with copper loops going through buckets of water and ice and then looped on fans. That approach would require constantly adding ice... I've already got the air flow, so I'm wondering how to condition it... By the way, the other short term option is to use a portable air conditioner and exhaust it through the window or the fireplace. I haven't heard good things about those units... Comments appreciated!