Nords could be more specific about solar panels, but IIRC, you pay HECO retail for your electricity used from the grid but can zero out some or all of your KWHs with your solar panels. But, even if you MORE than zero out your kWHs, you still owe about $20 or so (we would also owe this if we turned our master switch off). It's all the monthly fees HECO charges just to be a customer and to be connected. Then, the electricity is roughly $.25 or higher, depending on prevailing oil costs.
HECO charges $16/month for the privilege of being connected to their rock-solid grid voltage. (Part of the challenge of getting off the grid is starting large loads on your home's tiny 3 KW grid instead of the local utility's multi-megawatt generators. Refrigerators & vacuum cleaners have huge starting surges that transiently hammer grid voltage and make life hard for sensitive electronics.) In exchange for that monthly net-metering fee, HECO will compensate power production by carrying forward the excess on a rolling 12-month spreadsheet. Our PV production varies about 25% peak-to-peak from winter to summer, so it's nice to carry over the summer excesses to the winter months.
Above 10 KW of home PV capacity, HECO decides that you're no longer a residential customer but rather a generating plant. You'd be expected to pay a monthly "feed-in tariff" of at least $25 and they'd buy your electricity at wholesale rates (~18 cents/KWHr) instead of compensating at retail. I briefly looked into it but calculated that it's not cost-effective until your array is hundreds of kilowatts.
HECO also charges monthly fuel fees as part of their rate structure, which means their rates vary monthly. This year it's been as low as 20 cents/KWHr and as high as 33 cents/KWHr. Their electric bills are frankly confusing as hell and they probably like it that way.
HECO's billing system is also 20 years old so it can't directly read our "smart" meter, which no doubt suits their (human) meter reader employees just fine.
Also, re: solar, not just anyone can connect to the grid here. It is "rationed" as to how many can sell excess to HECO. Don't know the particulars, but think Nords touched on this before. Your KWHs may vary.
Well, technically you can connect to a grid without the utility knowing about it. The technique is known as "guerrilla solar". But eventually their billing department flags the dramatically lower bill and they send out a fraud inspector to see if you're running an extension cord to a neighbor or a street lamp. If you have a pending (but not yet approved) net-metering agreement when the fraud inspector shows up at your door, then... well, as M_Paquette says, "hilarity ensues". The dedicated guerrilla solar experts evade this by actually canceling their utility accounts, installing their array, and then resuming their electrical service under a new account number (and a different history of power consumption).
A net-metering agreement with HECO requires a licensed electrician's signature on the application, which also involves a building permit (and perhaps the neighborhood's HOA approval). If "grid penetration" in your neighborhood is more than 10% (the neighborhood grid's total PV generating capacity divided by the power consumed in that neighborhood's portion of the grid) then HECO reviews some sort of data to determine if the local grid voltage will be destabilized by variable sunshine and variable loads. If the penetration approaches 15% then HECO expects the next poor [-]sucker[/-] net-metering applicant to pay for an engineering study that could cost over $10K.
That grid-penetration ratio is probably not a problem in most Mainland areas where the grids are much more interconnected. Or maybe Mainland grids are easier to destabilize because they're such large, chaotic, poorly-tracked, and inadequately-controlled systems.
Ironically HECO employs many retired Navy nuclear-trained submariners. Unfortunately they're mostly the engineers, not so much the business-process staff.
We've had our PV array down for over three weeks. With all the saws and air compressors and power tools running on our familyroom renovation during that time, I'm dreading the next electric bill... I wouldn't be surprised to be over $200.
