Up Hill House - page 7 of 23

  • Estimating heat energy for 2012

    April 7 Update: Using a different method I estimated  that we used 903 kWh for heat energy in 2012, that’s 16% of our total energy use. That would have cost us about $117 (using $0.13 per kWh).

    We don’t have a full 12 months of data for our heat, but using heating degree days (HDD) and performance thus far we can estimate that we used 591 kWh (+/-20%) for heat in 2012. That’s 11% of our total energy use for the year.

    Here’s the math…

    Read more...
  • We're net positive for 2012!

    Pie chart showing circuit usage YTD
    Pie chart showing circuit usage YTD
    Bar chart showing circuit usage per month
    Bar chart showing circuit usage per month

    Year Summary

    We’re net positive for 2012! We used 5,601 kWh and generated 8,856 kWh for a net surplus of 3,256 kWh. We used an average of 15.3 kWh per day.

    Read more...
  • Home Performance App Upgrade

    I’ve updated our home performance app at, NetPlusDesign.com.

    Screenshot from new app.
    Screenshot from new app.

    At the beginning of the year I put together a simple online tool that displays our energy and temperature data on a daily and hourly basis. It gave me an easier way to track and visualize our energy usage on a month to month basis without a bunch of spreadsheet work. The heat maps provide an easy way to quickly find days of high energy use and see what else was going on that day. This helps me understand why usage might be high on a particular day.

    Read more...
  • November performance

    Chart showing monthly usage, generation, net and hdd
    Chart showing monthly usage, generation, net and hdd

    We used 498 kWh and generated 615 kWh for a net surplus of 117 kWh in November. This is our ninth consecutive surplus month. We’ve generated a surplus of 3,622 kWh so far this year, guaranteeing we’ll be net positive for our first year of operation.

    Read more...
  • Temperature and energy use observations

    As I continue sifting through our performance data, I’ve been focusing lately on outdoor temperatures and their relationship with our heating and cooling energy use. These are a few of my observations.

    70 percent of time period was below 68 degrees
    70 percent of time period was below 68 degrees

    We have 9 months, 274 days, 6,576 hours of temperature data, from February 1 to October 31. Of those 6,576 hours, 4,635 outdoor temperature hours were below 68 degrees F.  Roughly 70% of the recorded time period has been below 68 degrees F.

    Read more...
  • Correlating HDD with heating energy use

    Chart showing poor correlation between HDD and heat energy use
    Chart showing poor correlation between HDD and heat energy use

    I spent a few of the Sandy storm days indoors and decided to indulge my inner nerd. I’ve been tracking all our house performance data using monthly spreadsheets, which can make it difficult to filter data or look for trends across months. So I downloaded mySQL and imported all our energy and temperature data into the database. This is the first in a series of posts on what I find as I sift through the data.

    Read more...
  • October performance

    Total usage vs production in kWh as of Oct 31
    Total usage vs production in kWh as of Oct 31

    October was overshadowed by the events of the last week. Despite the best efforts of Hurricane Sandy we are safe and dry at Up Hill House. We had plenty of strong wind gusts, but not nearly as bad as the costal regions. We were prepared for the worst. We stocked up on water and easy to prepare meals. We have a small propane burner that can be used to heat water or simple cooking. We packed the chest freezer with ice. We filled the bathtub for flushing and the cistern was full for the farm critters. Thankfully the power never went out.

    Read more...
  • September performance

    performance chart september
    performance chart september

    Fall weather arrived last month. More rain and clouds with cooler nights. We generated 883 kWh in September, down 15% from last month, but still about 37 kWh better than predicted. We generated on average 29.4 kWh per day.

    We used 292 kWh, our lowest month yet. That’s down 7% from the previous month. We used the air conditioning only 2 days and heating for 1 day. We used 9.5 kWh for cooling / dehumidification, and 5.9 kWh for heating. Together that’s 5% of our month’s total usage. We generated a 591 kWh surplus this month, our 7th surplus month in a row.

    I changed the format of the table a bit. Months now run down the table instead of across.

    Read more...
  • NY State SREC Update

    I follow the SRECTrade blog for New York related solar news. You can find the latest update here. It contains this bit of unwelcome news.

    Read more...
  • Green Building Open House 2012 Reminder

    Just a reminder. The Green Building Open House Tour, sponsored by NESEA, and the National Solar Tour, sponsored by the American Solar Energy Society, is October 13 this year from 10 to 4.

    Read more...