Six Years with Solar

It's been six years since I installed solar panels on my roof and things are still going great:

87% of my home's electricity needs have been provided by the sun.

75% of my installation costs have been recouped through incentives, reduced reliance on my utility's electric supply, SREC sales, and referral bonuses from my installer.

$0.18 per kilowatt-hour is my effective cost for electricity that the solar PV system has produced so far, including all taxes and fees. That rate is falling about one cent per quarter; if that trend continues the system could potentially pay itself off in another 4-5 years.

What else has happened?

Not much since my year two update. I'm still very hands off, the system just silently does it's thing.

There's far more installs in my neighborhood now: a few dozen within a three minute walk of my house, and easily one hundred in the surrounding area.

That's the good news, but there have been a few hiccups.

SREC Market Recovering

In August 2015 the price of a single SREC was $165 but a year later it had dropped to $28. The price fell even further in 2017.

With the passage of the Maryland Clean Energy Jobs Act (CEJA) in May 2019, the SREC market has been recovering nicely.

This legislation requires 50% of Maryland’s energy to come from renewable sources and 14.5% from in-state solar, by 2030.

Since the passage of CEJA the price has jumped up to $65 and since the beginning of the COVID-19 pandemic has further increased to $80. SREC Trade reports a 23% drop in build-out rate over the previous twelve months. If I had to guess, there's a lot of installations on hold as consumers priorities shift toward their health and that of their families.

Cost of Electricity

The cost of electricity over the past couple years has been on the decline, ranging from $0.10 to $0.12 per kilowatt-hour from my utility (including supply, delivery, taxes, and fees).

My effective rate for electricity I produce is $0.18 per kilowatt-hour and falling. Within two years I could easily see my effective rate being less expensive than from my utility.

Monitoring Discrepancies

Over a six year period my production meter recorded 350 kWh more than SunPower's monitoring software (roughly 5 kWh/month on average). Occasionally the SunPower hardware needs a reset, has recording issues, or SunPower's data processing backend isn't working properly.

I've adjusted some of my tracking spreadsheets to account for this and allow trueing-up with the production meter periodically as it's a far more accurate instrument.

Production Shortfalls

It's possible that the discrepancies listed above could account for some of the production shortfalls I've seen. Even taking the shortfalls into consideration, the system is still only producing 92% of it's warranted output on a monthly basis.

I could submit for my installer to reimburse me for this shortfall. They've given me the runaround the last two years and frankly it isn't worth the hassle.

Continuing On...

Six years in, the sun is still shining. I'm still pleased with my decision to install solar PV panels on my home.

If I bought another property, I wouldn't hesitate to install solar PV there as well.

Last Modified: 2021-01-17

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