Because so many people asked for contact info, here you go:

Our installers were Horizon Energy Systems. Kurt Newick (408-761-2029) was our liaison with Horizon and he was wonderful to work with. Kurt seems entirely committed to the widespread deployment of Solar power generation more-so than grabbing commissions. Good dude. Do recommend.

Full disclosure: We did have some difficulty during the install. Horizon was extremely forthright in dealing with the situation and I would have zero hesitation in working with them again. Actually, we are already talking about upping our system’s generation capacity.

Solar Summary.png

As of the last couple of days, our household has gone from a consumer to a producer of electricity. Our 3.2kw, 16 panel, solar generation system is now online! With a peak generation of 2.7 kilowatts, we generated about 21.6kWh today alone.

You can see both current and historical data via this this site (iPhone app, please??!?!).

Beyond being good for the environment blahblahobviousblah, the solar system will pay for itself in something pretty close to a decade (the huge rebates help alot!). If PG&E actually starts paying for surplus electricity in the next couple of years as promised under AB 920, it may pay for itself sooner (and we might add panels to accelerate the payback — more below).

As well, it is just really satisfying to watch the little dial on the electric meter run backwards. This morning as the panels started to warm up and the meter was just starting to tick backwards, I had Roger watch the meter while I toggled the electric dryer on/off. “Holy cow! That makes the dial go the wrong way really fast!”. Yup, sure does– now think about how fast/slow various devices make that dial go!

No, I don’t entirely believe these numbers… but, better than being just a consumer!

Our installation is relatively straightforward, though there are elements on the cutting edge at this time. Namely, it is using Sunpower panels combined with M210 micro-inverters from Enphase.

That warrants explanation; there are two sorts of common solar installations; large inverter (potentially multiple) and micro-inverter.

In many, there is a single inverter that converts the DC electricity generated by the panels into AC to be fed to the house and grid. Single inverters are typically measured by the kilowatts they can handle and, not surprisingly, the more power they can handle, the more expensive. Not only that, but inverters often achieve peak efficiency at somewhere around 70% to 90% capacity.

I.e. single inverters are fairly cost effective and SunPower’s inverters have nice web based monitoring tools (our panels are from SunPower), but don’t often give you much of an upgrade path.

Micro-inverters are — as the name implies — small inverters where there is one inverter per panel. The inverters are then connected together into chains and have the smarts to synchronize the phase of power generation before feeding the sum total generated power back to the grid.

Micro-inverters have several advantages. First, in a large inverter system, you typically have a series of panels that feed the inverter. If any one panel is dirty, shaded, or otherwise running inefficiently, it drags down the output of the whole system. Micro-inverters bypass that issue entirely in that every panel operates independently.

Secondly (and of potential critical importance depending on AB 920), micro-inverter based systems are significantly easy to upgrade in that you can mostly just add pairs of panels and micro-inverters into the existing system. There is obviously a limit as to the number of panels per run per phase and, at some point, you will need to run new feeder lines into the panel to handle the power.

In our case, we have room to add three, maybe four, more pairs without any additional hardware installed.

Finally, micro-inverters need to have quite a bit of smarts to be able to communicate with the other inverters and make sure all the power is being generated in phase, etc. Thus, micro-inverter based systems tend to have very good monitoring solutions. For the Enphase micro-inverters, our installation included an Envoy gateway that collects information about our system and relays it back to the Enphase web site.

Quite a lot of fun to see the animations and monitoring tools. Via the full administrative user interface, I can also see all anomalous events and the system will automatically call for help if something goes terribly wrong.

All in all, it is a really great system. The marriage of technology with production value on that web site obviously scratches my geek itch while feeding power back to the grid is good for the Bay area (notably, rolling blackouts occur during peak power demand which also coincide with peak solar power generation — little systems like ours will help to reduce the load on the overall grid by distributing power generation)!

The installation was done by Horizon Energy Systems. Kurt Newick acted as the liaison with Horizon and he is absolutely committed to the cause of seeing solar used far and wide. Kurt is professional, friendly, and an all around great person to work with!

We had a slight issue with our electrical during the installation — understandable given the goofiness of Eichlers — and Horizon took accountability for the issue and did everything possible to fix the problem while ensuring that we were completely happy with the installation.

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10 Responses to “Solar!”

  1. Steve Dekorte says:

    Congrats! Very cool.

  2. Peter Bierman says:

    Wow, the animation of power per panel over the course of a day is a great visualization! It’s cool to see shadows move across the panels. (BTW- your link to your data requires a login.)

    Do you still have an old style analog power meter? If it spins backwards during daylight, I presume PG&E is only stiffing you if your monthly net usage is negative? Any gotchyas expected once you get “upgraded” to a smart meter?

  3. annbb says:

    Congrats on reducing your carbon footprint!

  4. Dan Sully says:

    Bill – is yours a grid-tied system, or do you have batteries for storing generated energy in times of power outages?

  5. Todd Thomas says:

    So if you are generating energy that goes back to the grid you don’t get paid for it? That kind of sucks.

  6. Mike says:

    I’m not familiar with the California laws/requirements one has to meet, or the process one must go through, in order to add solar panels to their house. Do you have to get the OK from local government first, or can anyone who’s a single-family homeowner add solar panels, as long as it’s up to code?

    I’m asking because I hope to move to California soon. I won’t be able to afford a mortgage for a while, but when I do, I’d like to make sure that, wherever I move, I can add a solar panel setup. Are some towns/cities more conservative about what you can add to the exterior than others?

  7. bbum's weblog-o-mat » Blog Archive » Enphase Energy’s Envoy says:

    […] This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 2.5 License. Widgets « Solar! […]

  8. Luc J says:

    Congrats with your system. We installed ours a year ago and it has been producing more that expected, making up for the theoretical degradation of 10-20% over 20 years.
    Even better, we got a loan to buy the system, this way we got more revenues from it that we have to pay back, already the first month.

  9. Paul says:

    We’re getting a similar PV system installed right now. I wrote to Enphase about their flash-tastic website and it turns out they are testing an iPhone-friendly version:
    From their customer service: “Feel free to play around with it and send us feedback.”

  10. Mike says:

    Hi, I got my system legalized and turned on about 2 weeks ago. It was a tough road to convince the city of San Jose that my Solyndra panels were ok for my residential roof. But it is on now. Yesterday, 4/25/2011 I made 14.5 kWH for the day. I’d like to see your daily kWH numbers as our systems are the same size. I have one Sunny Boy Inverter, I wonder about my losses related to it vs the microinverters.

    4/14/2011 13.6
    15-Apr 16.1
    16-Apr 12.1
    17-Apr 17.9
    18-Apr 6.6
    19-Apr 13.6
    20-Apr 14.2
    21-Apr 15.9
    22-Apr 9.3
    23-Apr 12.5
    24-Apr 13
    25-Apr 14.5


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