Clip on 80W Panel Door Way Fan - See Pinned Comment for Understandings.

OK this set up is for pumping the cool night air into and through the building - between the hot summer days.

And it's used for pumping the warm day air in - between the cold winter nights.

Lets assume that the summer day temperatures are 35* - 42*C and the night temperatures are say 16 - 22*C.

The cool night time temperature kicks in around say 10 pm to midnight and fizzes out around 7 to 9 am..

That is a good 7 - 9 hours of cool night air time, to pump the cool night air into the building.

This works. It keeps the average building internal temperature down by 6 to 12*C.

In winter, the outside sunny area temperature is say 26*C, and the nights are 2 to 9*C, I can suck all that cold air at floor level out of the building and fill it with warm air, heating up the inside from say 10am to 4 pm...

That keeps the internal temperature about 18 - 20*C.

With power costing ~45c a Kwh - an 80W fan uses about 25c a day to heat and cool a whole building.

This system is climate and season dependent - and will work well in some areas and not others and in different parts of the year... and not others.

For instance, when the summers are REALLY hot - like 43*C or more during the day and it's still 33 - 35*C at 3 or 4 am... Your better off sealing up ONE room and insulating that place and using air conditioning.

And in a really cold winter, where it's say 2 or 3*C at night and 7, 8, 9, 10*C during the day - your better off using reverse cycle air conditioning... and heating your sealed up and insulated room, on the cheap like that.

This system of heating and cooling - in my part of the world works well for the type of climate, the range of temperatures and the typical summer and winter temperatures.

Some summers are cool, to mild to fairly hot, at low 30's to high 30's and low 40's - and some are just fucking roasting - like 45 - 47*C.

Some winters can be mild and warmish, and some can be fucking freezing.

But if you live in very hot equatorial areas or polar regions - your climate will and can be very different to my typical weather patterns and temperatures and seasonal variations.

Here where I live, TYPICALLY - about 4 to 6 weeks in the hottest part of summer and the coldest part of winter - this system can't be used...

But out of 52 weeks in a year, that leaves about 40 weeks where it can be used for fresh air and good to great low cost heating and cooling.....

That is around say 280 days out of 365 days, where I can get great heating and cooling - some times for 4 hours or 8 hours so the cost and the time of use can be 5c a day to 30c a day...

The idea that we must have an all or nothing solution, that works all the time is wrong...

This system works really well most of the time, and at very low cost.

The sun heats up the place in winter, and I keep that heat in over night... and I pump the cold air out from the floor level, during the day, and the sun heated air, warms the place up...

And in the summer it's reversed, the planet loses the heat at night to space and I move that cool air through the building and keep the heat out during the day.

And while all the other dumb arses, living with big reverse cycle air conditioners, wood fires etc., and piss poor insulation, are paying HUGE bills for their heating and cooling, I am doing very well with fresh air and and exceptionally low power bills.

Use your brains, this is what they are for.