It’s the start of the summer in the UK and we’ve recently had our first heatwave, it was unbearably hot a couple of weeks ago so I decided to start developing a home-brew “air conditioning” system based on a number of designs around the Internet – taking the best components from each and refining them to produce an optimised and improved design. The goal of this project is to create a system that provides a large amount of cooling, but at very low expenditure (this project will initial cost me less than £20, excluding postage, whereas most professional units start from £80-150).
Phase 1 Design
My design will be primarily based around a car radiator, initially using ice as a coolant. The cooling mechanism is really open to whatever you have available, for example one person pumped water from a fresh stream nearby (unfortunately I do not have one of these). My ice will be sourced from a standard freezer, so really this will just be a displacing heat from the room the unit is in to the kitchen – but the water can be frozen at night or when it is cooler weather. In later phases I’d like to investigate alternate cooling methods, mainly chemical and mechanical systems, but the majority of obvious options are likely to be fairly expensive.
- Expanded polystyrene tank (£1.20 ex. postage)
- Carbonated drinks bottle (2l) filled with ice
- Car radiator (£8 ex. postage)
- Pond fountain pump
Other components:
- Hose pipe (I’ve ordered two lengths of garden pond piping, one 12mm wide and one 38mm – £6 inc. postage)
- Jubilee clips
- Silicon sealant
- Wood base
I have obtained a small pump from a garden fountain that was in the garage and not being used, it will pump water from the polystyrene tank in to the radiator that will then flow back in to the tank. The bottle of ice will hopefully cool the water down as it flows around it. A desk fan will push air through the radiator to begin with, although if the project is successful I’d like to replace it with a proper fan rig.
The radiator will provide a large surface area for the cooled water to act over, and the polystyrene tank will help increase overall efficiency by preventing potentially non-beneficial heat loss (ideally the cold will be distributed around the room, rather than remaining near the unit). I will need to measure the performance of the device once it is assembled but based on examples I’ve seen on the web I’m confident it will be at least partially successful.
Potential limitations:
- As it is a fairly low-grade pump I am concerned about whether it will be able to completely fill the radiator.
- I have not yet determined how long each container of ice will last, this may prove to be an issue as there is a limit to the freezing capacity I have available.
So far I have acquired the radiator and pump, and am just waiting for my tank and piping to turn up before I can begin assembly. I’ll also need to obtain a piece of wood to mount it on, but this isn’t a blocker.
At some point I intend to set up graphs to record the temperature of the room the unit will be in, to hopefully show a before/after comparison. The rest of my construction materials should show up soon and I’ll be able to begin building the system next week.