Chip Skiff & Garret: It is great what you guys are doing. As soon as I sell the house I am in I will be building an "off grid ready passive and active solar thermal mass house. I Can't wait.
I would like to add a couple of points to help clarify the reality for anyone interested. (This is what I try to get across to my students at the college I teach some night classes at. The course is Energy Sustainability Engineering Technology)
Housing:
1. Near net zero housing is attainable now for a small premium. The building envelope and structure / site design are the key.
2. The biggest impediment to #1 above are our old building codes and local bylaws - things like requiring that building be lined up with the street, etc.
3. Building codes are to a large extent driven by the building material industry. Innovation is discouraged.
On the bigger picture regarding energy (Electricity) use:
1. Electric motors in industry account for between 75-80% of NA electricty use!
2. Most NA industries could cut their electricity use by up to 20-30% by correct sizing of motors. Our tendency is to oversize motors for their application by at least 25% - most 3 phase motors have their worst efficiency and power factor at 75% load.
3. A large number of motors are driving either fans or pumps, ie: centrifugal loads = Variable torque loads. The biggest potential energy savings is the application of variable speed drives on these loads. A fan or pump slowed down to 50% speed to meet the process need instead of throttling the valve or dampers used 13% of the energy while still giving 50% flow. This is where we can make some differance.
4. AC Variable speed motor control is now available and reliable to very large HP sizes - like 10,000hp. And yes, there are a lot of fans and pumps running out their in the thousands of HP. The compressors on all new gas pipelines have these multi thousand HP drives on them for this reason.
5. A big wind turbine is about 2.2Mw = around 3,000hp
6. A typical sawmill has about 2000 - 5,000HP, a pulp mill or mine upwards to 60,000HP
Just some thoughts.

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