2014 Solar Report

Solar 2014

We just finished our first full calendar year (i.e., January to December) with our solar PV system and it was a great one. Renovus (our solar installer) gave an amazingly spot-on estimate: they (well, their software) figured our 12-panel, 3.92 kW system would produce 4494 kWh per year. As you can see we got 4434 kWh this year. Less than 2% off.

I had some perceptions that didn’t meet up with reality. For example, I felt this summer was unusually mild and much less rainy than 2013. It also seemed like we enjoyed a warmer and sunnier September too. The data doesn’t bear that out. August 2013 was the first full month the solar system was in operation, so comparing from that point onward you can see that 2013 outperformed 2014 in every month except December.

2013 2014
August 523.53 513.01
September 478.46 472.33
October 319.27 303.06
November 244.93 198.84
December 66.72 88.08

I’m pretty happy that 90% of our electricity needs are met by solar, but I obviously want to do better. We have 300 watts of kitchen recessed lighting that gets used a lot (at least 2 hours a day; likely more) and still hasn’t been switched over to LED. I have a bunch of vampire devices like the Playstation 3 and Wii that don’t get used much but waste energy nonetheless. There’s more we can do to keep moisture out of the basement which would allow the dehumidifier to run less often. I’d love to get to 95% in the next year.

I can’t neglect to mention that we may have increased our usage by having central air conditioning installed this past spring (also by Renovus; they recently added HVAC to their list of services). I still need to write about that. Before that we relied on several window units. I haven’t done any work to compare the electrical load of central air against 3 window units, but according to our NYSEG bill there’s no doubt we used more electricity:

Billing Period Average Daily Use Average Daily Temp
July 2013 7 kWh 73° F
July 2014 7 kWh 69° F
August 2013 9 kWh 65° F
August 2014 14 kWh 65° F

So despite a warmer July in 2013, we used the same amount of electricity in 2014. And despite the same average temperature in August, we used 50% more electricity this year, though this comparison doesn’t quite work since in 2013 we were away for 10 days that month. Still, it’s probably safe to say we’re paying for that extra comfort.

Solar Install Day 4

July 1. I’m in Bedford, Massachusetts for work while my favorite house project is being completed back in Ithaca. Fortunately my wife was able to take a few photos.

Our system is built with SunPower X21 panels, the most efficient on the market. I’ve read a lot of advice online that the cost of these panels aren’t necessarily worth the added cost if you have plenty of roof space (in which case you’re better off getting the best cost per watt you can). For our roof, though, these are perfect.

Solar Install Day 4 1

Solar Install Day 4 2

Perfect Painters put up their sign the first day they started work, but Renovus didn’t get around to putting their sign up until the last day of installation. I don’t mind both of us showing off some awesome solar work.

Solar Install Day 4 3

I took this photo of the finished work on July 4. Gorgeous.

Solar Install Day 4 4

The monitoring system isn’t fully installed yet, so for the moment the only way to see how much power is being produced is via the inverter’s LCD. By the end of Independence Day we had generated about 20 kWh.

Solar Install Day 4

See also:
Solar Install Day 1
Solar Install Day 2
Solar Install Day 3

Snug Planet Energy Audit

On June 7 Mary Kate and Maria came from Snug Planet to hold a one hour education session with us. We took some action from that: we replaced that horribly wasteful showerhead with the 1.5 gpm Niagara Chrome Earth. My wife also had me replace a bunch of faucets around the house with lower flow aerators (I’m less pleased about this and I’m not convinced it’s that important anyway, given how little time we spend in front of sinks).

Three weeks after the education session Blake showed up to perform the full audit. Like Mary Kate and Maria, Blake asked us about our goals for the house. It’s important to clarify which of comfort, saving energy, or saving money is your highest priority, since payback on the cost of remediation can be both difficult to quantify and difficult to achieve. The work can be expensive and natural gas is cheap (and will likely remain so for quite a while).

We walked throughout the house, going top to bottom, so Blake could do a visual inspection. There are 3 closets (really access doors into the attic space) on the third floor that Blake said would benefit from having their floors torn up and filled with insulation. This would render these spaces unsuitable for storage, but would help seal off the living space from the attic. The floor cavity underneath the storage and living space needs to be separated so air doesn’t travel between the two spaces. The walls would also benefit from being filled with insulation. That drywall has bulged and needs to be replaced anyway.

On the second floor the main takeaway was that after the house is buttoned up, it will be more important to expel moisture from the bathroom. Blake recommended a bathroom fan in the wall.

I don’t remember much of note on the first floor other than Blake’s advice to turn the range hood fan on when using the oven. As the oven begins to warm you may get unburned gas and carbon monoxide that’s best vented outside.

Like the attic I expected there would be plenty of work in the basement, and it did not disappoint. Using a nifty gas sniffer Blake found two (!!!) minor gas leaks.

Gas detection

The device is pretty cool, but it’s hyper-sensitive so you still want to verify there’s a leak with the old fashioned bubble test (where you apply a soap or soap-like solution to a connection and look for bubbles), which did indeed confirm those leaks. Fortunately no leaks were found in the gas line leading to the dryer, which I hooked up myself.

When Snug Planet came for the education session Mary Kate suggested a vapor barrier to seal off the basement floor, but Blake believed pouring more concrete (into the rougher section of the floor) would be sufficient. He was more concerned with the walls of the basement, which he said would benefit from being insulated with rigid foam boards. He also approved of my draining the dehumidifier into the sump.

As my home inspector pointed out, the doorway leading to the basement access (often called “Bilco doors” although I don’t know if mine is actually Bilco brand) needs to be sealed off because it leaks pretty generously. Fortunately Snug Planet has experience in that sort of thing:

There were a few other minor notes about the basement, but then it was on to my most anticipated part of the audit: the blower door test. The blower door is an adjustable metal frame (to fit just about any size door) that holds some kind of nylon-like fabric that blocks off the door except for a hole where a powerful fan fits.

Setting up the blower door

The fan speed is computer-controlled in order to maintain pressure of 50 Pascals. Apparently this number is a building performance standard, and like many standards its origin was a bit arbitrary. Blake mentioned that while experts desired a higher pressure, the fans of the era when the standard was established (the 1970s maybe? I forget) were only powerful enough to maintain 50 Pascals, and that limitation defined the paradigm.

Keeping things at 50 pascals

Fixing the internal pressure allows us to measure the amount of air flowing through the home in cubic feet per minute. Blake said our number was about average for a house of this size and age. In the attic you could feel air rushing through the access doors, which isn’t surprising considering the living space is connected to attic space with a vents to the outside. Also unsurprisingly, there was lots of air coming in through the basement door too. Once you get past the obvious stuff, though, it’s helpful to use tools that give you better visibility into your home’s deficiencies.

That’s where this thermography camera from FLIR comes into play. I imagine this works better when it’s winter and there’s a more substantial differential between inside and outside temperatures, but even in summer you can notice obvious deficiencies. In this photo below you can very clearly see the outlines of the floor joists, suggesting there’s little to no insulation in the cavities between them.

Infrared camera

As with the gas detector, though, these gadgets still require you verify their results, and again a low tech solution was useful: Blake had a short piece of wire he stuck into available holes (I still have many outlet covers removed from when we painted) feeling for resistance that indicates some kind of insulation was present. Sometimes he could hook into the insulation and pull some out in order to identify whether it was fiberglass or cellulose.

Unsurprisingly, our walls are sorely lacking in insulation. Some of the rooms did have some fiberglass insulation that came from some previous owner’s renovation (plaster and lathe removed and drywall installed), but for the most part the walls are empty. This problem is usually solved by punching holes in the wall and blowing in insulation. Because our house is covered by two different materials, each level of the house would be handled differently. The upper level, covered in cedar shake shingles, could be entered from outside like most homes. Stucco, however, is very difficult to patch in an aesthetically pleasing way and Blake said they’ll usually blow in insulation from the inside in that situation.

At the end of the audit, Blake asked us how he could best help us proceed with our goals for the house. As someone with limited time and skills, I figured getting estimates for the various solutions we discussed throughout the audit would be helpful for deciding what our priorities should be. The attic easily had the most to gain, and Blake ballparked that the work to rip up the flooring and install insulation throughout could be in the $3000 range. Other things we’re interested in, as mentioned above, are installing a bathroom fan and insulating the basement with foam board.

There are a handful of easy things I can take care of myself, such as putting insulation around some of the pipes leading in and out of the water heater (why in, you ask? thermosiphoning can pull warm water into the cold intake pipe). The gas leaks are best handled by an HVAC specialist. For the rest we’re waiting on word from Snug Planet on how best to proceed and how much it might cost.

It was a great educational experience and well worth the four hours total (1 hour educational session, 3 hours for the actual audit). The cost in New York is free or really low, so there’s little reason not to get it done. I have no basis for comparison, having only gotten one energy audit done ever, but Snug Planet was as friendly, helpful and knowledgeable as their reputation indicated. I’m looking forward to seeing what else they can help us with.

Solar Install Day 2

Most of the second day of work was related to the roof hardware, though as you’ll see below the meter was installed in the basement too. One of the poor dudes had to crawl into the attic to measure the locations of each rafter, which apparently are not evenly spaced (common in older homes, I’m told). It must have been hot as hell up there judging from how drenched in sweat he was. I’ve never been in the attic space above the third floor, and I don’t have much desire to visit.

The pitch of the roof is making the work harder than expected and they’ll have to continue the work tomorrow. They may have to return Monday as well.

Solar Install 06

Solar Install 07

Solar Install 08

Solar Install 09

See also: Solar Install Day 1

Solar Install Day 1

This is really the second installation day if you count the conduit and board put in place over a month ago, but I’ll consider that a “pre-installation” since the work today kicks off what should be an uninterrupted series of days that’ll end with Renovus switching the system on.

The inverter, electrical meter and monitoring system are in. Tomorrow the panels go on the roof and hopefully everything gets hooked up.

Solar Install 04

Solar Install 02

Solar Install 05

Solar Install 03

Solar Install 01

Snug Planet Energy Education

About two months ago NYSERDA approved our application for a reduced cost home energy assessment. This morning we had the first of what will be two visits from Snug Planet, a local energy efficiency contractor. Mary Kate and Maria came by for a one hour “Energy Education” session, during which we went over our energy goals for the house with tips on how to improve things.

I consider myself pretty well-educated on this subject, so there wasn’t a huge list of revelations that came out of the session. Still, the things we did learn are important:

  • Our shower heads use an enormous amount of water. Mary Kate has a plastic pitcher and stopwatch she uses to assess the flow rate of shower heads, and the one in our main bathroom lets loose about 8 gallons per minute. She says that might be a record. The shower wand on the third floor was a little better at 5 gallons per minute, but it’s still awful. The current federal mandate limits flow to 2.5 gpm. No wonder we run out of hot water so quickly…
  • We can improve the moisture situation in the basement with a vapor barrier that seals off the dirt floor. We currently have two dehumidifiers running in the basement, and during this rainy week they’ve each been using 5 kWh a day. That might be higher than normal days, but still, combined we’re using 10 kWh/day or 3650 kWh per year to keep the basement dry. That’s most of the annual 4800 or so kWh we expect to generate from solar panels. The only real downside to installing the vapor barrier is we’ll have to tear up the wood floor that covers a portion of the basement. It provides a clean and level base for our stuff, including the chest freezer. It might be worth losing it, though.
  • I already had plans to use a smart power strip (a current-sensing one in particular) and continue installing LED bulbs, but the visit is motivating me to get that done faster. Weeks ago I bought three MR16 halogen replacement lamps from Amazon for the living room in order to determine which one had the best light. I’ll put up a review of those later. I also need to think about LED flood lamps for the kitchen.

Great visit overall. I can’t wait for Snug Planet to return for the blower test in a few weeks so we can see how leaky this house is.

17 Days to Go

The new breaker panel is in.

May 4 Update 1

I don’t think I’ve mentioned this before, but there used to be two panels here: one for each side of the house when it was a duplex. As I wrote earlier, the house has 150 amp electrical service. One panel got 100 amps and the other got 150. When the house was merged back into a single family home they kept the 100 amp feed from one meter and had a breaker from the 100 amp panel feed the 50 amp panel.

Now we’ve got one panel with bus bar rating of 200 amps (the solar installation requires something like 25% extra capacity) fed with the whole 150 amps.

The electricians were going to junk this old panel that wasn’t hooked up anymore, but I told them I wanted to keep it. 30 amps! I might give it a home near the new panel and solar equipment if there’s room.

May 4 Update 2

One of the posts in the stairwell was separating from the railing. The guys from Restore A Floor worked on pushing them back together and will eventually drive a lag bolt through to make sure it doesn’t separate further.

May 4 Update 4

For now they’ve applied that super-strong glue used underneath the stairs. I don’t have a before picture, but the current gap is a huge improvement.

May 4 Update 3

The new floor patch is in and it looks amazing (compare with the old patch). Once it’s refinished it’ll be impossible to distinguish from the original wood.

May 4 Update 7

They also started applying wood filler to the gaps between boards.

May 4 Update 8

We finished applying a second coat of Sherwin-Williams Pewter Tankard to the dining room on Thursday. Goodbye peach…

May 4 Update 9

Hello gray. We love it. The light fixture is on its way out too.

May 4 Update 6.1

We still have the living room and bathrooms to do, and then we’ll tape off and paint all the trim at once. I’d like to get the downstairs trim done as soon as possible, as Restore A Floor removed the old quarter round molding and will be installing new molding after all the floors are done.

20 Days to Go

A few updates:

We have a move-in date: May 21. The past 18 days of ownership went by in a flash. All we’ve managed to finish so far is to paint 4 bedrooms and prepare the downstairs for painting. We did get most of the dining room painted this evening, but we had to stop when the sun went down because the house has no electricity. More on that later.

The guys from Restore A Floor continued their repairs yesterday. They fixed up the subfloor underneath that poorly done patch.

May 1 Update 2

They took apart the wood paneling covering the underside of the stairs so they could shore them up. The stairs creak quite a bit and the highest two steps don’t seem firmly secured. The underside of the other set of stairs is easily accessible from the basement. They’ve started the reinforcement process by adding some kind of strong glue underneath, with plans to add more wood later.

May 1 Update 1

They also recommended adding a floor jack in the basement underneath a load bearing beam that appears to be sagging. To get it in some of the wood covering the basement floor needed to be cut and I figured they’d do a cleaner job of doing that than I would.

May 1 Update 3

This morning the electrician calls me to say they’re inspecting the outside of the house to prepare to start work. He asks if I’m nearby to let them inside. At this point I’m 15 minutes away at the veterinary hospital plus I’m expecting the floor guys to be working today. Luckily (?), when I contact the owner to ask if I should delay the electricians, I learn he has car trouble and can’t make it anyway.

I arrive at the house in time to see the electricians cut service to the house:

May 1 Update1

Then in the afternoon I take a stroll back to the house right as they begin hooking it back up again:

May 1 Update2

The new service entrance cable is in, but the panel in the basement isn’t quite ready.

May 1 Update4

At some point the house was converted to a duplex and so two meters were needed to bill each resident separately. Then someone combined everything again and one meter has sat empty since.

Empty meter

That’s now been cleaned up:

May 1 Update3

As I mentioned we had to work without electricity this evening, but power should be back on at 10 am tomorrow, just in time for Tim Moon to resume work.

My home inspector had assumed the house had 100 amp service, but when the guys from Renovus were examining the house they discovered it actually had 150 amp service, presumably supplying 100 and 50 amps to the larger and smaller parts of the house respectively when it was a duplex. We weren’t sure 100 amp service would be sufficient for the central air conditioning I’d like to put in some day, but 150 should be plenty.

Residential Energy Audit APPROVED


Speaking of NYSERDA, I just got an email from them approving us for a reduced cost energy assessment. NYSERDA offers reduced price home energy audits through their New York Home Performance with ENERGY STAR® comprehensive home energy assessment program (for most people it ends up being totally free). The application is here and relatively painless (you do need old energy bills or a waiver for a home you’ve just purchased).

NYSERDA also offers a bunch of low-interest financing options if you can’t afford to get everything fixed right away. One of their plans charges right to your energy bill and payments are capped at the amount of energy cost savings that the fixes are expected to produce. I’d rather not finance at all, but their money is relatively cheap and I’ve been writing checks to contractors left and right lately.

The next step for us is to pick someone to perform the audit and I’ve already done that: I’ve heard great things about Ithaca-based Snug Planet and I’ve already contacted them to schedule.

Kicking off Solar

Our good friend Keith recently started at Renovus Energy (as of this writing the site basically doesn’t exist, though it promises a launch eventually), the premier solar installer in the Ithaca area. He gave us a great housewarming gift: coming over 10 minutes after we closed on the house last Friday to take our deposit for a 4.1 kW solar electric system with the just-announced 21.5% efficiency, 345 watt SunPower X-Series panels.

This morning we took the next step and I signed a bunch of paperwork for NYSERDA to approve the rebate Renovus will collect on our behalf. This is the first time I’ve ever signed documents on an iPad. Really forward-thinking, this company.


Also from Renovus was Joshua to perform the site evaluation. This guy was incredibly friendly and fearless on the roof. He used some shade analysis tool (it looked like one of these, but I can’t be sure) to determine that everything looks pretty good up there: decent roof pitch, minimal shading and the side of the roof facing south is away from the street, so I don’t have to care about how the array looks.

Honestly, I wouldn’t care anyway. I’m interested in maximum power output and it’s just a bonus that the back side of the house happens to be ideal. We’re also planning on symmetrical placement of panels on each side of the roof, so the layout will fulfill my OCD desire for balance.


Now we wait 6 weeks or so for NYSERDA approval. I can’t wait.