How cool is elimination of the need for external energy altogether? Think of a house as a free-standing energy system – without need for external energy sources to maintain habitability and comfort. So what makes a building sustainable?
Wikipedia defines Green Building here… Does this definition make sense to you?
I hung on the word efficiency as a cop out. Efficiency means to limit consumption of external resources – minimize waste.
This seems like a much better goal to me. Efficiency is wimpy.
Do you know that a good sized, 60×60 ft, house squanders enough energy as sunshine every year to add up to $73,000 as propane, or $175,000 as electricity? That’s a bunch of wasted energy.
Modern building methods create obstacles – best practice – and building codes create a trap. Modern building practices, inspired by energy code invites most buildings to squander almost ALL the energy that nature gives them.
Given the huge amount of resource that nature presents, it’s ridiculous that any house inside the the 45th parallels need external energy at all.
Energy isolation requirements appear as “r-factor”, “u-factor”, solar heat gain factor, SHGF. Regulations continue to reduce the amount of energy a structure can absorb from the environment. They specifically dictate the MAXIMUM amount of energy a building is allowed to absorb from the sun as SHGF.
While it makes sense to limit the maximum amount of energy a structure should lose from an internal heat source; it makes no sense to dictate how much energy can absorb, especially during cold months. Isolation is the design standard of modern housing.
The superior goal is absorption balanced with loss and storage. This is simple. If a building can store enough during time of surplus, to carry over a time of shortage, then external energy is not required.
This presentation presents a few “tricks” and a new way to design the environmental interfaces, so that your building can harvest and store energy to be energy independent, self regulating, and adaptive to sun’s position using very simple, and almost free materials.
If you’re further North, you may need more storage though.
4 thoughts on “Energy Free Buildings”
we build houses as status symbols, not domiciles. lotta energy around a house we fail to consider when setting up the rules. Have to quit the box idea of a house.
The least expensive way to store solar energy for A/C or Heat is in a large tank of water. Dollar for Dollar, a water tank stores more than 10 times as much energy as Nickel Iron or Lithium Iron Phosphate batteries [$500 vs. $15,000]. You just need a 10’x12′ room with a thermostatic vent.
Calculate your total heating or cooling BTU requirement for your house for 5 days with no sunlight and size your tank to match. An 8’x8′ – 6′ deep membrane lined box tank will hold 1,680,000 BTUs at 165 degrees F [max] and 95 degrees F [min]. If you need more BTUs of storage, just use a bigger tank.
Add 2 4’x8′ Solar Thermal panels on each end of your solar wall to capture the heat for unlimited domestic hot water. Use a solar powered multi-split heat pump [with de-superheater] to provide A/C [Summer], Heat [Winter] and Hot Water all year..
The water tank stores 35 degree F cold water in the summer and 165 degree hot water in the winter. The tank has 12″ R50 foam insulation all around so it occupies a 10’x10’x8′ volume. The load is less than 100 lb. per sq. foot. The tank is made of 7/8″ plywood and angle iron with a membrane liner and insulating foam sheets between the liner and the plywood.
I built 2000 gallon thermal reservoir into the design to store domestic hot water. You’re right – this is by far the cheapest way to store energy within a thermal mass for domestic hot water. By my calculation it stores about 2M BTUs. But the container and the insulation, and making sure it doesn’t leak added up some bucks.
The big win was the thermal mass that cradles the living space. The thermal cradle for the living space, 1000 tons of dirt, cost almost nothing.
The dirt was well – dirt cheap. The water jug ran about $4K by the time I had it installed, insulated, and not leaking.