Qapla
Veteran Member
If I counted right, one array has 30 panels and the other has 33. Why the difference? or was my count off :confused3:
25 kW Solar power project in Iowa.
- Thread starter Redneck in training
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OP
Redneck in training
Elite Member
Actually there is third array also with 33 panels under construction being completed before year end unless the weather gets too bad. If I tell you why I did that my wife would laugh at me. I din't want it sticks to possible future airplane runway. The longer arrays are ofset several feet west so they can be longer.
sodamo
Super Star Member
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- Big Island, HI
- Tractor
- Bobcat CT4545 LS XR4140H (Mine) BX2380 (wife’s)
Why thank you. We only use ceiling fans to augment air movement, but find that really only necessary when we have a lot of people. We do have propane fireplaces to take the chill off at times but mostly ambiance.
Amazing how costs have come down since I started my system (2006). Now I could get twice the wattage for 1/3 the cost for panels. Batteries may cost more. I'm very happy with my system.
Look for to seeing your progress and hearing how it works.
David Sent from my iPad using TractorByNet
Amazing how costs have come down since I started my system (2006). Now I could get twice the wattage for 1/3 the cost for panels. Batteries may cost more. I'm very happy with my system.
Look for to seeing your progress and hearing how it works.
David Sent from my iPad using TractorByNet
OP
Redneck in training
Elite Member
We finished the last array today. I still have to connect all cables to the breaker box and connect it to the grid. That is few more hours of work I will do tomorrow.
Here is a summary of the project:
96 Canadian Solar 250W panels.
96 Enphase inverters. All divided into 9 center connected strings because of voltage rise is a big issue here.
Expected peak AC power about 21 kW. Expected yearly production about 32000 kWh or 88 kWh/day.
All panels are mounted on Ironridge rails supported by wood structure anchored by 52 reinforced concrete piers.
It took about 4 weeks of work of two people (my wife and I) to complete. Two weeks of drilling holes and making concrete piers and two weeks of building the racking and assembly of the system.
After adding all bills together it all cost $55348.01 or 2.31/W DC before tax rebate. Hopefully we get federal tax rebate of $16604.40 plus $3000 Iowa tax rebate.
Total cost after rebates $35743.607 or $1.49/W DC. We overshot original budget by about $2200 underestimating cost of some electrical gear and especially fees imposed by the local electrical coop.
I will post pics tomorrow.
Here is a summary of the project:
96 Canadian Solar 250W panels.
96 Enphase inverters. All divided into 9 center connected strings because of voltage rise is a big issue here.
Expected peak AC power about 21 kW. Expected yearly production about 32000 kWh or 88 kWh/day.
All panels are mounted on Ironridge rails supported by wood structure anchored by 52 reinforced concrete piers.
It took about 4 weeks of work of two people (my wife and I) to complete. Two weeks of drilling holes and making concrete piers and two weeks of building the racking and assembly of the system.
After adding all bills together it all cost $55348.01 or 2.31/W DC before tax rebate. Hopefully we get federal tax rebate of $16604.40 plus $3000 Iowa tax rebate.
Total cost after rebates $35743.607 or $1.49/W DC. We overshot original budget by about $2200 underestimating cost of some electrical gear and especially fees imposed by the local electrical coop.
I will post pics tomorrow.
OP
Redneck in training
Elite Member
Drilling holes for concrete footing. Week one.
Making footings. Week one and two.
Footings for one array. End of week two
.Building first array. Week three.
Ditching for the main cable. Week three.
Last batch of panels on improvised forklift.
All done. Week four.
daugen
Epic Contributor
Very impressive. Wind, solar, hydroelectric, wave energy... we need it all.
I'd sure like to hook up my all electric house to your array...cord might be a bit long.
And since you have good wind in your area, next step is to get a windmill in there. But for no moving parts, you can't get much better than solar.
Some think solar unattractive, but at the end of a big field,
is the corn going to complain? I wonder if passing airplanes will get "flashed" on a sunny day.
I hope this works out well for you long term. In the short term, thanks for doing your part.
I'd sure like to hook up my all electric house to your array...cord might be a bit long.
And since you have good wind in your area, next step is to get a windmill in there. But for no moving parts, you can't get much better than solar.
Some think solar unattractive, but at the end of a big field,
is the corn going to complain? I wonder if passing airplanes will get "flashed" on a sunny day.
I hope this works out well for you long term. In the short term, thanks for doing your part.
OP
Redneck in training
Elite Member
It is all done. Just missing one grounding clamp and Enphase cable to one panel (I think that when they measured the cable the guy cut it on wrong side of the connector). The chunk of the cable with the connector and the coupler should arrive in mail in few days.
I was thinking about wind for some time but found the wind generators way too expensive and requiring maintenance 120 ft high. At the cost of PV panels wind is dead on arival.
I was thinking about wind for some time but found the wind generators way too expensive and requiring maintenance 120 ft high. At the cost of PV panels wind is dead on arival.
daugen
Epic Contributor
It is all done
Well, you're just about 1000 miles from me. Wonder what size extension cord I need...:licking:
Well, you're just about 1000 miles from me. Wonder what size extension cord I need...:licking:
OP
Redneck in training
Elite Member
I purposelly put the cost "as built" there so whomever is interested can do the math.
Qapla
Veteran Member
Since some if you guys seem to be well versed in Solar ... any idea if and how and how much it would cost do put in Solar to power my 5 ton A/C-heat pump package unit?
OP
Redneck in training
Elite Member
Since you live in FL your unit does primarily AC I am guessing. If I am not mistaken 5 ton=17.6 kW. Heat pumps have about 400% efficiency therefore the unit has about 4.5kW compressor. Actually better approach is to figure how much space you have available in example on the south facing roof. Based on the size of the HP unit (I am guessing) you burn about 23000 kWh/year. PV system producing 23000 kWh/year would have to be about 15.5 kW. The actual cost would then depend on DIY or turn key and location. Roof being the cheapest. I got quote for turn key $3.90/W in Iowa before tax rebate. We built our ground standing system DIY for $2.26 before tax rebate. Gainesville has solar coefficient 5.17 in other words 1 kW of installed PV power would produce (in average) 5.17 kWh/day.
If you would do it DIY I would recommend microinverters. It will increase the cost by about 7% but you will not burn anything or kill yourself. It is much easier to deal with single panel producing 30V/9A then a string of panels producing 600V/10-15A.
Just remember though about those micro-inverters is that the heat in the Fla Sun from May-Sept. will have them in the 110-120*F range or higher up on the roof under the solar panels. They have not been on the market long enough to make a judgement about how they hold up.
That would be my biggest concern.
That would be my biggest concern.
OP
Redneck in training
Elite Member
You have to use longer standoffs for better cooling.
schmism
Super Member
can you talk about the micro inverters?
I get that they generally have proprietary cabling and connections to the panels, but how does the AC side work. Do you simply use a junction box and wire nut 3/4/5 (whatever) AC leads together to join that many micro controllers all putting out 2 amps into a single 6/8/10 (whatever) amp AC lead? I assume they phase correct on there own somehow with electronics?
do you just run those AC legs back to a receptical/service panel to connect to the house/barn/shop?
is it possible to pull direct DC off the microinverters for battery charging or DC lighting? can you use a backup battery bank and microinveters together?
I get that they generally have proprietary cabling and connections to the panels, but how does the AC side work. Do you simply use a junction box and wire nut 3/4/5 (whatever) AC leads together to join that many micro controllers all putting out 2 amps into a single 6/8/10 (whatever) amp AC lead? I assume they phase correct on there own somehow with electronics?
do you just run those AC legs back to a receptical/service panel to connect to the house/barn/shop?
is it possible to pull direct DC off the microinverters for battery charging or DC lighting? can you use a backup battery bank and microinveters together?
OP
Redneck in training
Elite Member
Yes. Microinverters have special cabling with connectors spaced either portrait or landscape. It makes all connection quick and easy. You can chain up to 17 inverters/branch. Each branch has to have its own 20A breaker. They are grid comutated and produce "pure" sine wave. If the grid voltage drops below 210V or increases over 260V they disconnect from the grid. There is a possibility to use them also off grid. The battery feeds a "master" inverter that makes the microinverters think that the grid is up and running.
We have 96 inverters in 9 branches. Each branch is center connected directly to a breaker and via breaker box to the main cable and grid.
Qapla
Veteran Member
According to the data with the A/C unit it has a "total unit amps" of 30.7 and it is single phase 220-240v
At 240 volts that would be 7369 watts needed to operate the unit.
I would assume that would be for A/C-Heat Pump operation since it takes an additional breaker to run the heat strips. The heat strips are actually optional and the unit can run without them. In fact, the heat strips could be connected to the grid while the A/C-Heat Pump is run from the Solar Power.
As far as roof area, I have an East/West roof - no South facing roof. However, I have 30 acres so finding a place to put a free standing array would not be a problem. I am also capable of DIY.
With this information is it possible to give a more bottom-line type figure for the panels and inverters needed. As far as a frame, I am sure I could build something if need be.
At 240 volts that would be 7369 watts needed to operate the unit.
I would assume that would be for A/C-Heat Pump operation since it takes an additional breaker to run the heat strips. The heat strips are actually optional and the unit can run without them. In fact, the heat strips could be connected to the grid while the A/C-Heat Pump is run from the Solar Power.
As far as roof area, I have an East/West roof - no South facing roof. However, I have 30 acres so finding a place to put a free standing array would not be a problem. I am also capable of DIY.
With this information is it possible to give a more bottom-line type figure for the panels and inverters needed. As far as a frame, I am sure I could build something if need be.
