EcoRenovator - View Single Post - New (?) Idea for dealing with summer cooling with solar panels

AC_Hacker · 01-26-13, 10:44 AM

I completely agree with randen, he's spent a lot of time researching & testing & building and it's working for him.

The chart you have there... I'm curious about it. Is it a chart of solar energy falling on a surface, or is it a chart of energy output from a particular solar collector? Also, I'm not sure that I understand what tilt angle the measuring device or solar collector is mounted at. The reason for my questions is that raw insolation values need to be de-rated for tilt and also for specific collector inefficiencies. So your thinking that went from insolation to area required for a particular amount of heat may be adversely affected.

Regarding the house part of your overall effort, here is a photo of the first Passive House:

Architectural beauty could be a topic for another discussion. But I have seen drawings of this house, and it incorporates quite a large number of great ideas that could be included in the house you have in mind.

Most notable is the large window exposure (large gain) on the side that will benefit from solar exposure. Also there is the small window area (small loss) on the other exposures.

Not visible form this photo is that the stairways from ground floor to upper floor are at the back of the house and have a separated air space from the front (solar side) of the house. I know that the stairway is not directly involved in fresh air or heat recovery. The only heat it gets is what might leak through the very thick wall. So it serves as a buffer for the back of the house, from the cold German winters.

On the bright side of the house, there is a vertical stack that goes from the ground up about 1/3 the height of the house. This is the air input for the house, and there is an underground run of ventilation pipe that warms incoming winter air, and cools incoming summer air BEFORE it gets to the Heat Recovery Ventilator.

Also not visible, is that Passive House building techniques incorporate a design that has very thick insulated walls, and arranges structural members in such a way that thermal flow through wood (R-1) is not continuous from inside the house to outside surface. They call this 'eliminating thermal bridges'. Almost none of the currently constructed houses use this technique. However it is required in several Scandinavian countries.

So, what all this house-talk means to you is this: If you can massively reduce your heating an cooling needs, then utilizing the fairly low intensity of solar energy & geothermal energy & water heat storage (compared to high energy density fossil fuels) your ideas regarding solar and heat pump optimization of your home will be well within your reach.

It's important to realize where we are in history. In particular in the history of petroleum energy development. We have benefited from, and adapted to an environment that is richer in cheap, dense energy than any era in the history of mankind.

We have become accustomed to this situation. Our transportation has adapted to it, our food production has adapted to it, our housing has adapted to it.

But just because we have become accustomed to it, does not mean it will continue.

Your project is really headed in the right direction.

Best,

-AC

01-26-13, 10:44 AM	#6
AC_Hacker Supreme EcoRenovator Join Date: Mar 2009 Location: Portland, OR Posts: 4,004 Thanks: 303 Thanked 723 Times in 534 Posts	Solar House... I completely agree with randen, he's spent a lot of time researching & testing & building and it's working for him. The chart you have there... I'm curious about it. Is it a chart of solar energy falling on a surface, or is it a chart of energy output from a particular solar collector? Also, I'm not sure that I understand what tilt angle the measuring device or solar collector is mounted at. The reason for my questions is that raw insolation values need to be de-rated for tilt and also for specific collector inefficiencies. So your thinking that went from insolation to area required for a particular amount of heat may be adversely affected. Regarding the house part of your overall effort, here is a photo of the first Passive House: Architectural beauty could be a topic for another discussion. But I have seen drawings of this house, and it incorporates quite a large number of great ideas that could be included in the house you have in mind. Most notable is the large window exposure (large gain) on the side that will benefit from solar exposure. Also there is the small window area (small loss) on the other exposures. Not visible form this photo is that the stairways from ground floor to upper floor are at the back of the house and have a separated air space from the front (solar side) of the house. I know that the stairway is not directly involved in fresh air or heat recovery. The only heat it gets is what might leak through the very thick wall. So it serves as a buffer for the back of the house, from the cold German winters. On the bright side of the house, there is a vertical stack that goes from the ground up about 1/3 the height of the house. This is the air input for the house, and there is an underground run of ventilation pipe that warms incoming winter air, and cools incoming summer air BEFORE it gets to the Heat Recovery Ventilator. Also not visible, is that Passive House building techniques incorporate a design that has very thick insulated walls, and arranges structural members in such a way that thermal flow through wood (R-1) is not continuous from inside the house to outside surface. They call this 'eliminating thermal bridges'. Almost none of the currently constructed houses use this technique. However it is required in several Scandinavian countries. So, what all this house-talk means to you is this: If you can massively reduce your heating an cooling needs, then utilizing the fairly low intensity of solar energy & geothermal energy & water heat storage (compared to high energy density fossil fuels) your ideas regarding solar and heat pump optimization of your home will be well within your reach. It's important to realize where we are in history. In particular in the history of petroleum energy development. We have benefited from, and adapted to an environment that is richer in cheap, dense energy than any era in the history of mankind. We have become accustomed to this situation. Our transportation has adapted to it, our food production has adapted to it, our housing has adapted to it. But just because we have become accustomed to it, does not mean it will continue. Your project is really headed in the right direction. Best, -AC __________________ I'm not an HVAC technician. In fact, I'm barely even a hacker... Last edited by AC_Hacker; 01-26-13 at 10:47 AM..