Progress to Date

  • Original Loan Amount: $204,000.00
  • Balance at Beginning of 5-year Goal (1/1/08): $188,983.82 @ 6.00%
  • Balance at Refinance in February 2009: $148,000.00 @ 4.625%
  • Outstanding Balance: $0.00 (PAID IN FULL!!!)
  • Latest Payment Date: April 2011
  • Latest Additional Principal Amount: $17,623.22
  • Amount Ahead of Schedule (since refinance): $121,462
  • Time Ahead of Schedule (since refinance): 7 years 10 months
  • Interest Saved Last Month: $23,972.48
  • Total Interest Saved: $28,435.55 ($1,037.74 on original mortgage; $27,397.81 on current mortgage)
  • Months Remaining in 5-year Goal: 20
  • Average Monthly Principal Needed to Meet Goal: N/A (Goal achieved)
  • Progress List Explained

Thursday, December 17, 2009

Passive Solar

I stayed home today because I was sick. It was a bright sunny day outside, but cold (the high was 18 F). Still, I decided to try an experiment. My wife and I have noticed that on sunny winter days, we can shut off the heater and open the front door (southern exposure), letting the sun shine in through the glass outer door. As long as it does not get cloudy, the sunshine on the front of the house -- with the door open -- is enough to maintain the interior temperature, and often is enough to warm the house several degrees. We don't usually do this when it's as cold as it was today, however, but I decided to give it a try. Even with temperatures in the mid-teens outside, the passive solar trick warmed the house by one degree over about six hours. That's six hours we didn't have to burn natural gas to keep the house warm. Plus, it made the dogs happy to soak in the sunshine for a few hours.

I wish we could use this trick more often, but since it only works in bright sunshine, it's not practical on days when we are at work for 8+ hours. The short winter daylight hours and the potential for passing clouds would thwart the experiment. If only we could teach the dogs to open the door when it's sunny and close it back up when it's not...

5 comments:

RainyDaySaver said...

I have a similar trick: I wrench open the curtains in the morning to let in all the sunlight. I've never checked the thermostat, though. We're also lucky that our home is also southern exposure. I'm curious to see how the open front door would work, but our screen door is only half glass. The curtains get closed when the sun goes down or one of us gets home, whichever is first, to keep out the cold.

Copeland said...

I just discovered your blog and love it! We are also aggressively paying off our loan, have no desire to carry debt.

Speaking of passive solar, I have a line of house kits that are *totally* designed for passive solar, check 'em out if you like, and congratulations on focusing on the REAL American dream- debt-free sustainability.

Middle Way said...

We take advantage of this as well. Some days, even cloudy ones, our sunroom will get 4 degrees warmer than the house and I too just open the door and let the heat diffuse into the house. It also allows us to use that room in the winter without cranking on the fireplace there.

Hey, you never know what your dogs are capable of if you don't try! Hope you are feeling better.

change is a good thing said...

This is great! Our new home is almost all windows to the south, so we'll definitely be trying this out. Thanks for the tip. Happy holidays!

Anonymous said...

My Aunt used to do something similar. She had a small front porch windows on three sides and a door to the house. By mid morning the porch would heat up on a sunny day and she would open the door to the porch. It would heat up the living room and kitchen quite well.