OP
Redneck in training
Elite Member
Attached is estimate for 15kW system for your location. It will cost about $2.20/W DIY or about $3.90 turn key.
25 kW Solar power project in Iowa.
- Thread starter Redneck in training
- Start date
Attached is estimate for 15kW system for your location. It will cost about $2.20/W DIY or about $3.90 turn key.
A system of this size is not a good DIY first time project. I do not know your background or experience but from the questions you are asking I would assume that this is a first attempt at a PV installation. I would strongly suggest you retain an engineer with experience in this area. I am a retired EE and have designed systems in many locations and
environments and the learning curve is pretty steep for a project of this size.
There are companies doing installs on private land who pay a pretty nice fee to the landowner. I am not trying to throw a wet blanket on your idea. I am just being realistic.
environments and the learning curve is pretty steep for a project of this size.
There are companies doing installs on private land who pay a pretty nice fee to the landowner. I am not trying to throw a wet blanket on your idea. I am just being realistic.
OP
Redneck in training
Elite Member
I am a risk taker. I will spent money on installers when I get stuck.
MotorSeven
Elite Member
Red, why do you need such a large system? I'm with ya on solar and I think that will be my next big project(after the barn, a swimming hole cabin, a loop trail on the property, and and). Anyway, for a single family home and grid tied you should not need much more than 8-10KW(I was thinking 8KW for me). 25KW is a beast and that runs the cost way up.
I can't wait for you to document this build!
I can't wait for you to document this build!
OP
Redneck in training
Elite Member
We have 100% electric house. Heating is the single largest power user. We burn 39000 kWh/year. I added a shop last fall that also has to be tempered to at least above freezing because there is toilet and shower. So our house is a power hog. When I am going to build the racking I will build it to accommodate at least 20 or 30 panels more. I will add them later when I retire and will want to keep the shop at higher temperature and possibly also AC in the summer.
Now it all hinges on an ability to obtain a loan.
OP
Redneck in training
Elite Member
The bank we have mortgage with would give us a loan but they don't want to deal with the reporting paperwork required by the state for participation in Alternative Energy Revolving Loan Program (AERLP). AERLP will give us interest free loan for 50% of the expense only if a bank give us the other half. I asked for 50k only because 25k AERP loan requires simple application and can be approved anytime. Application for larger loans have to be submitted before certain deadline and require more complicated approval process. I think the low interest rates (if you can get a loan) make it financially viable project.
Stimw
Elite Member
So after you take $20,000. from your neighbors, friends, family and every taxpayer in the US you will still owe $33,750.00 which you will recoupe at the rate of $21. a month. At $21. a month it will take you 133 years to break even if the loan was interest free.
Am I still missing something?
JeffInCO
Bronze Member
I installed a 5.5kW system last year (not DIY). Here in Colorado, about an hour straight north of Denver, I made about 9 megawatt-hours of electricity in the first year at a value of about $800.
A few thoughts:
1) PV salespeople will factor in expected electricity cost increases. Watch out that they don't assume exaggerated appreciation rates.
2) 25kW is a huge system. Watch out that you don't overbuild, as your utility may pay you a lower rate (their average generation cost per kwh, rather than what you pay them per kwh) if you generate way more than you use. In my case, my system makes about 2/3 of my annual use.
3) My understanding is that micro inverters are more cost effective for small systems and central inverters for large. However, if micro inverters make it possible to DIY, the game may change.
4) By using micro inverters, you are fixing the voltage between the array and your breaker box to be the AC line voltage (240 volts AC). With a central inverter near your breaker box, the wiring between the array and inverter could be at 400-500 volts DC at half the current. Smaller (cheaper) wire could then be used.
5) I had to pull an electrical permit and also a structural permit for the panel mounting. I had to have stamped structural plans. You may or may not need permits/engineering, depending on local rules.
Jeff
A few thoughts:
1) PV salespeople will factor in expected electricity cost increases. Watch out that they don't assume exaggerated appreciation rates.
2) 25kW is a huge system. Watch out that you don't overbuild, as your utility may pay you a lower rate (their average generation cost per kwh, rather than what you pay them per kwh) if you generate way more than you use. In my case, my system makes about 2/3 of my annual use.
3) My understanding is that micro inverters are more cost effective for small systems and central inverters for large. However, if micro inverters make it possible to DIY, the game may change.
4) By using micro inverters, you are fixing the voltage between the array and your breaker box to be the AC line voltage (240 volts AC). With a central inverter near your breaker box, the wiring between the array and inverter could be at 400-500 volts DC at half the current. Smaller (cheaper) wire could then be used.
5) I had to pull an electrical permit and also a structural permit for the panel mounting. I had to have stamped structural plans. You may or may not need permits/engineering, depending on local rules.
Jeff
OP
Redneck in training
Elite Member
So far in Iowa we don't need permit to build it. We need it only inspected by certified inspector. But I will verify it before I spend money. We burn about 39000 kWh/year so I will need about 30kW system to break even. I checked historical trend of power cost increase in Iowa. It is about 2.8%/year but the trend is not a smooth curve. We pay wholesale rate for our geothermal and heat pump heating (we have two systems, geo for our house and air/air heat pump for the guest room located in the shop building). The rate increased about 4% every other year so far. Retail rate increased at lower rate though. In fact it went down for some time. We are on coop that is non profit so we pay the actual cost to deliver the power. Mid American Energy (major power generator in Iowa) want to build a nuclear plant. Since I work on similar projects I know that 50% cost overruns are the norm and my guess is after the dust settles and the blame game stops our electric rates will jump significantly.
I decided on microinverters because I will have to deal only with low DC voltages while working on the system during day light. It will cost about 10% more in hardware but it is much safer to do DIY.
I decided on microinverters because I will have to deal only with low DC voltages while working on the system during day light. It will cost about 10% more in hardware but it is much safer to do DIY.