Pruning for PV

Any day now we will begin installation of a 4.5 kW photovoltaic solar system on our roof with my company Sandri Energy. In order to get more sun for the system (and meet minimum state rebate requirements) we pruned our silver maple tree. To do the work we had John D. and his friend Gordon return to help us out. Spartan was up on the roof directing which branches to cut John was in the tree and Gordon worked on the ground. We cut 3 medium sized limbs. The amount of sun hitting the westerly part of the roof went from 69% to 81%. Overall, it is difficult to notice any difference to the canopy.

Pruning a tree ropes climbing

I have never been to a ticker tape parade with confetti, but I imagine this is what it is like.

I have never been to a ticker tape parade with confetti, but I imagine this is what it is like.

Limb falling from high up in tree

Two things make me queasy: surgery and its associated “blood and guts”, and watching John high up in the tree do his thing.

loading up a trailer with tree branches

Thank you to Thom for lending us his trailer.

Pointing to which limb to take down.

Pointing to which limb to take down.

John Duda and his friend Gordon make a great team! Thank you both!
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How to grow fresh air

I recently watched this TED talk entitled How to Grow Fresh Air. It has significant implications for our existing buildings that have poor air quality and for our new buildings that are being built to super-tight standards. If the power goes out and we are relying on our HRV’s and our ERV’s to bring us our healthy air Kamal Meattle says that we can rely on these three house plants to sustain us:

  1. Areca Palm  (Chrysalidocarpus lutescens) – Turns CO2 into O2 during the daytime
  2. Mother-in-law’s tongue (Sansevieria trifasciata) – Turns CO2 into O2 during the night time

  3. Money plant  (Epipremnum aureum) Removes – VOC’s


 

First floor photographs

Some photographs of the first floor:

View if one enters from the Vernon Street door.

View if one enters from the Vernon Street door.

Looking right upon entering through the Vernon Street door one looks up the stair well. The door facing the camera is the mechanical room, the door on the left is the first floor bath.

Looking right upon entering through the Vernon Street door one looks up the stair well. The door facing the camera is the mechanical room, the door on the left is the first floor bath.

granite scrap floor open floor plan

View from the living area into the dining area. The over-sized chase for the duct-work and solar piping serves to divide the spaces. On the far wall above the window is the heat pump.

open floor plan

Looking from the dining area into the living room.

Kitchen

Our kitchen still needs a fair bit of work. The half wall needs a bar top, the far counter is plywood, and there are some cabinets that need to be put in.

Mudroom with custom coat hooks

Last summer I built the coat rack using live edge cherry from one of our trees and hooks from our local black smith Pierce Street Ironworks. The door to the cold storage room still needs to be constructed.

First Annual Energy Usage Report

We have now been living in our home for over one year. Our home is completely run by electricity provided by WMECO, so this report is pretty easy.

Total energy usage from 2-10-2012 through 2-12-2013: 4197 kWh
Total cost: $701.96
Average temperature as reported by WMECO: 50 dgr F
Heating Degree Days
base 63F: 5564

Notes:
2012 was a leap year.
For whatever reason WMECO is not consistent with when they bill out, causing the annual usage to be represented by 368 days.
Three occupants for the entire period.
Due to line loss, for every one watt consumed three watts need to be generated

Other data points and related anecdotes:

  • For the winter, we have been happy with the heat pump set to 63 during the day and 59 at night.
  • For some reason the heat pump will heat the house past what it is set to. So, assuming no solar gain, the house is usually a couple of degrees warmer than the heat pump setting–and the heat pump will come on before the temperature has fallen. The only explanation I have for this is either the heat pump infrared thermometer is reading window temperatures, or it is inaccurate. The HRV thermometer appears to be accurate.
  • The house uses the first floor slab as a heat sink. During summer it keeps the home cool. Only after the heat wave, where the temperature was in the 90’s for 3 days straight, did I notice that the slab was warm.
  • A couple of readings from the HRV (heat recovery ventilator) (dgrs F)
    • 1/7/13 was sunny and in the low 40’s; the indoor temperature rose to 71. The night was in the upper teens, the heat was off, and we only dropped to 64 by 7:00am
    • 1/3/13 Overnight was in the lower single digits, the heat pump was set to 63 and the indoor temperature was 62.
  • The average humidity in the home so far this winter is around 40%

For comparison:
“In 2010, the average annual electricity consumption for a U.S. residential utility customer was 11,496 kWh […]. Tennessee had the highest annual consumption at 16,716 kWh and Maine the lowest at 6,252 kWh.” Source: http://www.eia.gov
Only 26% of US homes use electricity for heat. Source: http://visualeconomics.creditloan.com

My goal for next year is to be able to break down the usage into heating, cooling, cooking, refrigeration, ventilation, and hot water. This will require the installation of kilowatt meters by an electrician. The plug-in kind can only monitor the refrigeration and ventilation.

Cost Breakdown of Construction

The total cost of construction from clearing land until we were able to move in was about $161,100.
The final cost of completion will probably be closer to $165,000 as there are many small things that still need to be done, (trim, painting the third floor room, kitchen counter top, closet doors etc.). Also, one must keep in mind that my labor was free as well as the help of many friends and family. We received $15,100 in rebates and tax incentives bringing the total cost down to $146,000. Our 1500 square foot (S.F.) house cost $97.30/SF to build.

Cost breakdown by type of expenditure

Materials $90,245.09
Labor $60,655.35
Permits, fees, engineering $4,490.70
New tools $4,336.65
Equipment and tool rental $2,973.18
Fuel $1,559.44
Food $434.70
Trash, disposal costs $384.61
Other $290.36

Cost breakdown by construction area

Doors, windows, interior window trim, and extension jambs $18,787.55
Framing $17,840.95
Insulation (labor & material, includes foundation insulation) $15,946.51
Foundation for home and garage $15,248.53
Siding, soffit, exterior trim $13,965.51
Sitework $12,460.50
Plumbing (labor and material) $10,218.69
Other $6,933.52
Electrical $6,868.67
Roof (Material and labor both sheathing and metal) $4,801.80
Porch $4,010.37
Drywall $3,255.16
HRV & Ductwork (material only, no labor cost) $2,793.22
Paint (labor and material) $2,738.45
Heat pump (material and labor) $2,600.00
Floors $1,901.39
Stairs $1,643.28
Driveway $1,475.00
Tiling bathroom and kitchen counter $1,353.52
Create lumber from trees from site $740.36
Solar hot water (after rebates and incentives) $269.45

New look, New summary information, Updated Architectural Plans

We have made a bunch of updates to the blog: