Ventilating An Underground Chamber
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Given the following:
1. Location of the underground chamber is in a humid tropical location.
2. Facility is off-the-grid.
3. Chamber size is 20′ x 30′ x 10′ (height = 10′ ).
4. Sources of electricity are roof-mounted solar panels.
5. Chambers meant to shelter 6 people.
How will be the essentials of a design for a good ventilation system be like for such a facility?
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Replies
Boniface,
Ah, Dr. No, you are adding a bomb shelter to your tropical island hideout! Good idea!
If you are an off-grid survivalist, you can hook up a ventilating fan to a stationary bicycle. That is a very dependable bomb-shelter method of ventilation.
Otherwise, you'll need a battery bank to handle the fans on cloudy days and nights. You'll need to size your PV array and battery bank according to conventional off-grid sizing guidelines. And you'll need to size your mechanical ventilation system according to ASHRAE 62.2 guidelines (7.5 cfm per occupant, plus 1 cfm for every 100 square feet of occupiable floor area ).