I drove a ’78 Corolla to high school my senior year.
That car had a carburetor- and with the use of that term, I’ve risked estrangement from all six of our subscribers born after 1980, who have no need or wish to know what a carburetor is or does.
I could change the oil in the Corolla, replace the brakes, spark plugs, and even remove the carburetor, clean it, and replace it, all the while fancying myself quite the gear-head…until I got around guys that really knew cars, talking about overhead cams and glass packs and tossing about automotive jargon that I was certain they were making up on the spot to torment me. Sort of the conversational equivalent of taking someone snipe hunting.
The lesson learned all too early in life: it’s difficult to be an expert on very many things, because it takes a long time to become an expert in any one thing, especially if that thing and our understanding of it changes with new advancements. Besides, we don’t tend to live more than eight or nine decades, which is pretty brief.
Car parlance has nothing on the solar industry for coining cryptic terminology. I’ve been working at The Solar Company in Castro Valley for a year now, surrounded by smart, helpful people that are not stingy with trade secrets, and it’s still a weekly if not daily occurrence to hear words and/or phrases that send me scrambling back to a trade journal or the VP’s office for a definition or explanation (or crayon sketch). The Ops department, though forbearing, has begun to avoid eye contact when I come in, no doubt weary of the incessant inquiries.
We reach a certain compromise: we like to have some semblance of a grasp on what’s going on, while we become content to leave things like transmissions and refrigerant and torn meniscus and who’s driving the airplane to people who have devoted themselves to becoming experts in that field. There is one thing we insist on knowing: that the person in whose hands we’re leaving matters is truly an expert.
Back to industry idioms- a person considering solar for their home or business obviously has some intelligence by virtue of the fact they’re considering solar for their home or business. That person will hear words that are not obvious, such as string inverters versus microinverters. Uhh…
Sunlight travels one way, so if you’re going to make electricity out of it, it’s a direct current, or DC. An inverter causes DC to become an alternating current, or AC, which is safer and more cost effective, since the electricity dances back and forth along your wires and doesn’t lose its oomph. It’s a bit tricky how that happens, but the only REAL mystery so far is why they call the box an inverter, when it’s actually a CONverter.
A string inverter is a bit as the name implies: many solar panels all running on a single ‘extension cord’. A break anywhere in the cord or on any one of the panels interrupts power to all. A ‘chain is only as strong as the weakest link’ notion. This rarely matters, because rarely does anything cause a break in power flow either in the panels or the extension cord. The six-plug power-strip behind your entertainment center is basically out-of-sight, out-of-mind, while it quietly runs your TV, DVD player, stereo, Xbox, and lava lamp.
If string inverters work so well, what about these microinverters that all the movie stars keep talking about?
If Mrs. Adams has a giant, beloved chestnut tree in the front yard, her roof will be bathed in shade for part of the day. If there are solar panels in the shade, power in the extension cord string inverter system is hindered. If each panel has its own mini, or microinverter, however, the panels in the shade don’t interfere with the other panels that don’t take an afternoon nap. Each panel has its own independent little inverter. It’s less of a team effort, but doesn’t embarrass the panels that can’t run as fast all day long.
A microinverter system is intelligent when variables affect the amount of sunlight on different areas of the roof through the course of a day.
In either case, the one big box or the several little boxes turn free sunlight into power. Power is really expensive from someone other than Mr. Sun. I think the cabinet doors on the inverters should be in the shape of a goose- the things literally lay golden eggs all day every day.
If each panel has its own inverter, doesn’t that make the system more expensive?
If you’re paying $300 a month to the utility company this month, and $180 a month for solar next month, either with a string inverter or microinverters, how is that more expensive? If you’re writing a check, there is more hardware with microinverters; thus a bigger check. Yet still far less than what you’ll spend on a utility. And if the micro-inverter optimizes panel performance in shade, efficiency offsets expense. I’m going to have to answer ‘no’ on the more expensive query.
Admittedly, I don’t rightly know the percentage yield rate movements on the interest bearing fluctuations of financial accrual income totals compounded across quarterly maturity, but our customers are saying that solar power be less. If you’d like stats, there are a couple guys in our finance department that know. If I can get them to make eye contact, I’ll ask.