Cold Weather Update

This should be the last update.  The Mitsubishi min-split models we have are supposed to produce 100% down to a -5 degrees F.   This past January they got tested and preformed perfectly. We didn’t get to a -5 but did get to and near 0  a couple nights.   We had a two week spell where it was exceptionally cold, 12 day with the night time low in the teens and single numbers and only in the 20ds during the daytime..  The one mini-split in the family room kept the house between 68 to 70 down to around 15 degrees F,  below that we had to supplement it with the one in the bedroom.  We’d run the bedroom unit from noon ish or late afternoon  to 10:00 or 11:00PM.  It was our highest electrical usage so far, 1,100 kWh compared to last Jan at 992kWh..  Our old house averaged 1,200kWh for all the winter months (which didn’t include heat nor hot water).  Solar production was down a little because the penal were snow covered more days then last year.

Amazing performance.  The house was comfy, no drafts.   Now we are back to the cycle where the TV and cooking will,  on some day produce enough heat to turn off the mini-splits in the evening and over night to the next afternoon.


Well, at the one year mark,  we’ve achieved the Net-Zero goal.  Usage of 6,673kWh and generation of 6,722kWh.  That’s about a fine tuned as you can get.  Our final HERS rating was 11. The difference is the way we use the house and how the HERS rating works.

Our goals when we started were; A comfortable house; an aging in place floor plan;    an energy efficient; with Net-Zero an add on. And house that took on the appearance of a 1930s craftsmen.

I have to say all goals have been achieved.  We really enjoy the pace and the layout.  Because of the materials the house is comfortable: no drafts nor cold spots. The energy efficiently is amazing; in our last house with near the same square footage we used 12,000kW of electric just for plug load and cooling, heating and DHW was from propane.  This house used just 6,673kWh for everything.  Cost was $501.82 (not counting SRECs pay back)  a 90% reduction of energy cost from the last house.

There isn’t much more to say, so I expect this to be my last entry.  But I’m available for questions and any assistance  you my need.   My email address is




Closing in on ZERO

The summer’s been good as for energy usage and generation. April’s usage was 457kWh and generation was 435 kWh thus a $6.08 electric bill.  Since then we’ve over generated by 1,044.  Our electric bill has been $2.98 (the connection fee) for; May, June, July, August, September & October.  That’s 6 months with no energy bills and we have 1,044 kWh credit with JC P&L.

Our year ends with the November Meter Readings, around 11/25.  Our full year usage as of Oct 25  was 5,977 kWh and generation 6,493 kWh. I’m estimate a Nov usage of 678kWh and a generation of 434kWh thus ending the year with 6,612kWh usage and 6,819kWh generation.  I think we will be in 100kWh =/- of Zero.   That’s about as close as one can get.

Now our HERS rating is 11, but as I’ve written before the HERS model uses only design perimeters and assumes the a three bedroom 2.5 bath house has 2 adults and X children using electricity  and a different rate that just my wife and I use.

One of the things I’ve noticed is how many cloudy or partially cloudy day you get.   Oct was a good example we had 8 days where we only generated 9kWh or less and one day where we only generated 932Wh. That’s 26% of the days undegenerating. I don’t know how the estimates factor in cloudy days.  One estimate shows Oct should have generated 537kWh and actual was 480.

Watch for the full year report in early Dec.

I’m still waiting for NJ CleanEnergy to do it’s final review and cut me the check. Any day I hear.





Usage vs Generation Update

Just processed my August generation meter readings.   The house modeled at a HERS 16 because the model assumes the family size to match the bedrooms and bath rooms in the house.  It doesn’t allow the modification of the usage to match how the house will really be used.

Because on NJ’s Net Metering I adjusted our usage to match my estimate of what I though I’d use.   Now that I’ve got actuals up to the end of August I plugged in the last three month of the years estimate based on their matching months from the beginning of the year.


My estimate to usage is  6,929 kWh and my estimate usage is 7,078.    I’d call that a Net-Zero.


One Year Update

Last Winter

We’ve been in a year now.  What I can report is that the house lives up to ALL my expiations.  In winter there are no cold spots or drafts of chilly spots.  In 40f outside nighttime temps we may not run any heat at all.  We find the TV and appliances is enough to heat the great room and kitchen to around 68-70 degrees. and over night with our body heat plus Joe’s (our Border Colie) the bedroom temperature will go up, about two degrees over night.

On cold days and nights 20 to 40 the one mini-split in the great room is enough to heat the whole house (a 9,000btu @ 30.5SEER unit). When it’s below 20 in the afternoon, around 4:00PM as the sun is setting, like most house you feel a chill. So we run the bedroom mini-split for about two hours, then the one mini-split in the great room handles the hole house for the rest on the time.

Now, we didn’t have a very cold winter, I don’t think it ever got down to 10 degrees.  Our total energy costs for, Dec, Jan, Feb & Mar was just $383.  In the old house the EL cost was $583 plus about $3000 in propane.   A $3,200 savings just in winter.

I do need to build little shelters/roof for the mini-split’s condensers to keep the snow off.  One big snow storm buried them.

The hot water heater runs on  “heat pump” only mod, we’ve never had to let heating elements run.

Spring & Fall

The house just holds it temperature and nothing else needs to ne done,


The house holds it’s temperature, cold or warm.  So if its 68-70 in the morning just close the windows and it will stay there. If it goes into the upper 80s the house may gain a few degrees.  My may kick the great room mini-split on. With the outside temps at 90 plus we will run the great room mini-split up to around 10 PM, then off for the rest of the night.  We’ll run both the bedroom and Great room mini-splits when the humidity get uncomfortable .   The bedroom one for just about 2 hours.

In April our electrical bill was $6.08 with no credit generated, In May, June and July  the Electric charge was $2.89 (the grid linked fee) and we generated a 394 kW credit. I expect this month and maybe Sept the same. Plus We’ve created 4 SREC’s so far. I should get about 7 for the year.

I have a generated and a usage electric meter.  Both were installed late November when I was allowed to active the solar system.  So the generation was at it’s lowest point: last half Nov, Dec & Jan.  But in the next few days the generation meter will pass the usage meter.

HERS Rating

Because our life style doesn’t fit the model our HERS rating was only a 16.  My belief because there is only two of us living in the house our usage is below what the model predicts.  Since NJ is a net meter state (they pay us retail for our excess electric generation)  they’re not happy if I over generate to much. So I tried to match our solar system to our usage.  With the numbers I’m seeing I believe we will be very close to Net-Zero by our year end, Nov 30th.  I have the room for 4 more panels if I want to bust the out put a little or add an electric car.


So the house was 100% success.  My first goal was a comfortable house. And it really is in all aspects. The second goal was the energy savings and it looks like it will be close to a Net-Zero, thus around a $5,000 per year savings over out last house.

Solar Saystem Up & Runing

It’s Dec 15 and the solar system has been up are producing for a month.  It was as easy as I thought it would be and the getting through the Bureaucracy was as problematic as I expected.

The SolarEdge inverter and system is amazing.  It does all the work.  It reports to SolarEdge who ships the data to me via my PC and my phone. See report for today’s generation..