buzz4041
Well-known member
Teken you can go to wholesale solar site and they have tools to calculate along with the regional map indexes.
Solar electric
- Thread starter truckman5000
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buzz4041
Well-known member
hh76 what do you know about special requirements for hurricane areas. High wind loads.
hh76
Well-known member
Not a lot about huricane areas, but most municipalities have local codes for determining what wind load you should engineer for. Call your local building department to find out, then research racking manufacturers to find out which can meet those requirements. Most will have engineering reports ready for customers that will describe what configurations are necessary for what wind load you may encounter.
Teken
Well-known member
Will do and thanks for the feed back. I found a few that provided my general area. But, when Google came to our city my area was still under development and my home wasn't built yet.
Maybe this year or next when they come back with that little car to take new pictures my area will be listed on the new maps.
Teken . . .
The Enphase micro-inverters are all UL-1741 (anti-islanding) rated. There is no issue if you attach it to a live 240W solar panel in the sunshine and stand there with a male 240V plug in your hand. It won't shock you! The thing listens to the 240V wire for 5 minutes before it comes on-line. When the 60hz or the AC voltage drops out of allowable specs, it waits for it to come back into spec, and then starts the 5 minute coutdown before coming online. If anything goes out of spec, the 5 minutes starts all over again. These are NOT deadly inverters. The whole point of UL-1741 is to keep the grid safe for your neighbors, the grid owners, and the people who risk their lives every day working on it. If you're buying stuff that isn't UL-1741 rated and you are grid tying it, you are begging for a lawsuit. Only grid-tie stuff meant for grid tie! Use the stand alone stuff at your cottage in the woods.
Now, to answer Teken's question: one 220W 60 cell panel + one Enphase M215 = about .9kW per day (roughly, in an area with 5.1 peak hours of sunshine per day according to the NREL red book). If where you live is only rated 4.7 hours according to the NREL charts, then multiply .9kW * 4.7 / 5.1 and you'll get a rough approximation of your output. I break it down to individual panel output so you can multiply by the number of panels and inverters you can afford. The 220W panel in my reference is an Evergreen ES-E-220-FC3, not that you can buy them since Evergreen went bankrupt last year.
If you want a 4700W (DC) system for a relatively reasonable price from a "local" supplier to self-install, then hop on the Lowes website and get the $12774 Westinghouse setup. Use a Lowes card and I believe it'll knock off 5%. I think it also ships free to store, so borrow a pickup or trailer when it arrives. Panels weigh 42lbs each, and a pallet should fit nicely in a U-haul 5x7 trailer. I will warn you that the rack provided for self install with the Westinghouse system is only rated for 85mph winds. You'll need a structural engineer to make it go faster, and possibly a different rack entirely.
If you want to piecemeal a system together, grab a copy of the Enphase m215 approved 60 cell panel list, and search the web for the best prices you can find on a panel with a UL rating. Buy your Enphase inverters from Lowes with a 10% off moving coupon and they are slightly cheaper than the next best price i could find of $146 shipped. You buy all the Enphase cable you need for $21 per drop portrait length (1.0m plug spacing), or $27 per drop landscape length (1.7m plug spacing). Don't forget to purchase sealing caps for all the panels you cannot afford today, and a removal tool. Once you have cable, panel, inverter and sunshine, it's upto you to make it all meet all the applicable codes for your AHJ and your power company. They'll have some combination of hoops or cluelessness when you start talking grid-tie microinverter solar array. Your AHJ will probably want a single-line diagram showing how you intend to hook it all up. It helps to have this when you talk with them if they've not seen a micro-inverter setup before.
On a single 20A 240V branch circuit, you can add upto 17 M215 inverters. To use the 4700W (DC) Lowes system, you'll need two 20A 240V branches out of your breaker panel or sub-panel. If its a sub-panel, be sure the feeds back to your main panel are sufficient to handle the additional breakers. I believe code treats the new breakers as consumers (load) even though they are technically producers of energy (feeders).
Regarding the $500+ Enphase Envoy communications gateway, get the Westinghouse version off Lowes website and use a 10% off moving coupon, or a $25 off $250 coupon when you order it, puts the price under $500 either way, and it comes with the power line ethernet bridge. The envoy needs to go as close to your panel or sub-panel as possible. It listens to the power line communications signals from the inverters being pushed down the wire. The signal seems to drop off dramatically as you move away from the panel on a different branch circuit.
If you are only running one or two inverters and cannot justify the $500 envoy to watch your panels through the web, you could always just wire your panels through a standard meter base and buy your own stand alone meter. I'd get a 100A base with a built in disconnect if i was going this route. Recertified utility grade GE mechanical meters start at $33. It's not nearly as sophisticated as the Envoy which allows you to query individual inverter data through the website for things like DC voltage, DC current, AC frequency, AC voltage, and inverter output on 5 minute intervals along with trouble codes, power line faults, DC drop outs during the day, etc. but I know when you just have a handful of panels that the Envoy is the cost of a panel + inverter, if not more. If I had just 4 panels I'd rather have a fifth panel than a $500 gadget. If you had a sophisticated whole house monitoring system, you could probably watch array output with that. Again, you get no reporting from the inverters about faults without an Envoy. If you visit the Enphase website forums, you'll see some people have strange spikes in their voltage during the day that are dramatic enough to knock the inverters off-line. That's the sort of diagnostics that the envoy is good for.
Now, to answer Teken's question: one 220W 60 cell panel + one Enphase M215 = about .9kW per day (roughly, in an area with 5.1 peak hours of sunshine per day according to the NREL red book). If where you live is only rated 4.7 hours according to the NREL charts, then multiply .9kW * 4.7 / 5.1 and you'll get a rough approximation of your output. I break it down to individual panel output so you can multiply by the number of panels and inverters you can afford. The 220W panel in my reference is an Evergreen ES-E-220-FC3, not that you can buy them since Evergreen went bankrupt last year.
If you want a 4700W (DC) system for a relatively reasonable price from a "local" supplier to self-install, then hop on the Lowes website and get the $12774 Westinghouse setup. Use a Lowes card and I believe it'll knock off 5%. I think it also ships free to store, so borrow a pickup or trailer when it arrives. Panels weigh 42lbs each, and a pallet should fit nicely in a U-haul 5x7 trailer. I will warn you that the rack provided for self install with the Westinghouse system is only rated for 85mph winds. You'll need a structural engineer to make it go faster, and possibly a different rack entirely.
If you want to piecemeal a system together, grab a copy of the Enphase m215 approved 60 cell panel list, and search the web for the best prices you can find on a panel with a UL rating. Buy your Enphase inverters from Lowes with a 10% off moving coupon and they are slightly cheaper than the next best price i could find of $146 shipped. You buy all the Enphase cable you need for $21 per drop portrait length (1.0m plug spacing), or $27 per drop landscape length (1.7m plug spacing). Don't forget to purchase sealing caps for all the panels you cannot afford today, and a removal tool. Once you have cable, panel, inverter and sunshine, it's upto you to make it all meet all the applicable codes for your AHJ and your power company. They'll have some combination of hoops or cluelessness when you start talking grid-tie microinverter solar array. Your AHJ will probably want a single-line diagram showing how you intend to hook it all up. It helps to have this when you talk with them if they've not seen a micro-inverter setup before.
On a single 20A 240V branch circuit, you can add upto 17 M215 inverters. To use the 4700W (DC) Lowes system, you'll need two 20A 240V branches out of your breaker panel or sub-panel. If its a sub-panel, be sure the feeds back to your main panel are sufficient to handle the additional breakers. I believe code treats the new breakers as consumers (load) even though they are technically producers of energy (feeders).
Regarding the $500+ Enphase Envoy communications gateway, get the Westinghouse version off Lowes website and use a 10% off moving coupon, or a $25 off $250 coupon when you order it, puts the price under $500 either way, and it comes with the power line ethernet bridge. The envoy needs to go as close to your panel or sub-panel as possible. It listens to the power line communications signals from the inverters being pushed down the wire. The signal seems to drop off dramatically as you move away from the panel on a different branch circuit.
If you are only running one or two inverters and cannot justify the $500 envoy to watch your panels through the web, you could always just wire your panels through a standard meter base and buy your own stand alone meter. I'd get a 100A base with a built in disconnect if i was going this route. Recertified utility grade GE mechanical meters start at $33. It's not nearly as sophisticated as the Envoy which allows you to query individual inverter data through the website for things like DC voltage, DC current, AC frequency, AC voltage, and inverter output on 5 minute intervals along with trouble codes, power line faults, DC drop outs during the day, etc. but I know when you just have a handful of panels that the Envoy is the cost of a panel + inverter, if not more. If I had just 4 panels I'd rather have a fifth panel than a $500 gadget. If you had a sophisticated whole house monitoring system, you could probably watch array output with that. Again, you get no reporting from the inverters about faults without an Envoy. If you visit the Enphase website forums, you'll see some people have strange spikes in their voltage during the day that are dramatic enough to knock the inverters off-line. That's the sort of diagnostics that the envoy is good for.
Teken
Well-known member
Where2,
Thank you so very much for taking the time to reply and supply some feed back and insight to my questions. I believe in the not too distant future I will start off with a smaller system and grow it as finances allow.
I will definitely be purchasing the Envoy much later to defer the costs and also focus my finances toward devices that are reducing and making me money. As I have a GEM (Green Eye Monitor) from Brultech which can record and display net metered energy for 32 channels.
I have already started down the path with the local POCO and have to agree the process to get the net metering will be quite a task!
Any other feed back with respect to the Enphase or solar in general please do share.
Teken . . .
It might be that your power company is already in bed with the government and saw solar leasing as infringing on their regulated monopoly on you as a consumer. Where I live, I'm not allowed to compete with the power company. I can't sell clean power directly to my neighbor, even if I run my own wire to his building. I can only sell my power to the power company. If I generate substantial overages, the power company will only pay bulk rate for it (about half the typical billing rate per kWh).
Corporations operating as monopolies don't like competition. Check your state laws and regulations on power companies. In effect, a solar leasing company is "selling power" even though it originated on and may never leave YOUR property. If the system is generating excess power and feeding it back to the grid it becomes a third party producer which complicates things for the power company in terms of billing. The government goes along with the power company in this case because in many areas the government has a franchise fee or tax built into your power bill which varies according to consumption. Collecting tax revenue from third parties out of town or out of state for something that quietly sits in your backyard or on your roof is complicated when there could be thousands of these little leasing companies.
jacob_coulter
Well-known member
- Joined
- Oct 4, 2006
- Messages
- 333
I guess I missed the part in school where an "investment" that takes 16 years just to break even is considered good.
Also, your numbers are a bit off. Let's assume the sun shines every single day without a cloud and that a 5.0 kw system actually produces 5 kw at the meter (despite all the conversion losses)
5 kw x 5 hours of sun =25kwh
25kwh per day produced x $.07 (average cost per KWH in Phoenix) = $1.75
$1.75 x 365 days a year =$638.75
$16,000 system divided by $638.75 a year = 25 years to "break even"
And let's be honest, the solar panels and accompanying equipment are not going to last 25 years, and it would be prudent to say at least 1 out of 3 days are probably going to be cloudy and produce little to no electricity, in which case you're looking at something like at 35 years to break even.
I just like the "facts" to be known because there's a lot of ******** flying around about solar.
dahur
Well-known member
Becoming more efficient is the same as installing several solar panels.
Every bulb I have is a CFL. I have my TV, and components, the PC, router etc., on power strips.
Phantom loads add up.
Every bulb I have is a CFL. I have my TV, and components, the PC, router etc., on power strips.
Phantom loads add up.
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dahur
Well-known member
Could you please debunk my "break even" for me..?
My system wipes out the $1200 I was paying yearly for electricity.
The utility sends me a check every month totaling around $1000 for the year.
Since cloudy days, and losses are already included to arrive at those numbers....and my system cost $16,400. How many years for my "break even" ...?
Last edited:
OP
truckman5000
Well-known member
- Joined
- Mar 11, 2008
- Messages
- 1,440
What type of system/size of home do you have? What you said is my goal as in having the utility pay me, break even point sooner.
KWH. cost is .17 here.
You failed to account for the residual worth of the system, and a mathmatical function called "future value of money". At year 16, you don't throw the solar panels, inverters, racking, and wiring out with the bath water. You sell it on CL for $2/watt to the guy who couldn't afford it in 2012 or you sell it with the house when you move in 2019. This isn't like owning a disposable automobile where you give it away for scrap value at 16 years with 192k miles on the odometer, bald tires, and rusted out frame. In 2019, when you sell the house, the panels are still spitting out power every day the sun comes up. If you held the house all 16 years you compute it costs to "break even", the panels, rack and wiring still has residual value.
If you leave your $15k in the bank, at today's outstanding interest rates: 1.05% for a $10k+ MMA, you might have $15,159 in 12 months with compounding interest, if inflation is zero. Has anyone seen zero inflation? Does anyone foresee zero inflation? Without zero inflation, $0.07/kWh doesn't stay $0.07 for 16 years or even until you move in 2019. I know my POCO puts in for a rate increase every chance they get, using every excuse they can find to justify the increase. Curiously, the POCO seems to get an increase, just about every 13 months. In the last 16 years I've lived in my house my price per kWh has gone up 60%. All things considered, that isn't bad, gasoline prices more than tripled in 15 years. My POCO is burning NG which is at all time record low prices. As soon as NG cost starts going up, the POCO will be able to justify steeper rate increases along with their guaranteed 10% return on investment which according to the CFO of the POCO provides a "fair return" to investors.
Unless your POCO is looking for carbon credits to offset burning coal in one of their old power plants, don't expect the POCO to pay you for your system. In the southwest, as a requirement of California mandating that X% of a utilities power come from renewable sources, there is a demand for renewable energy sources. As a result, the POCO's gather up excess power generated by homeowners with renewable sources and sell that power across the state lines.
This is likely the scenario that the gentleman in NM is using. You basically Put up a solar array, sell it ALL to the POCO, they slide some numbers around some accounting books and sell those kWh to the guys with the mandate in California. The POCO makes a profit selling it. I've seen California POCOs soliciting people in Colorado to get their renewable energy credits, because the Calif. POCO has a branch in Colorado.
If there are rebates and credits to be had in MA, I'm sure it's all listed on the dsireusa.org website. Find your power company, in your state and see what they offer.
dahur
Well-known member
3.6KW with 16 225w Schott panels with 16 Enphase micro inverters. 2200 sq ft home with 5 ton 10 SEER AC unit used 4 months a year.
PNM rate is currently about .11 KWH.
Teken
Well-known member
Dahur,
I wanted to follow up with your installation and see if everything is still good. If you have any insight or additional feed back to provide it would be greatly appreciated.
Teken . . .
I wanted to follow up with your installation and see if everything is still good. If you have any insight or additional feed back to provide it would be greatly appreciated.
Teken . . .