New member from Iowa

[Cummins06TD]

Hey everyone. First off I'd like to say that I'm extremely happy to have found this site, vast wealth of information here! I'm a heavy equipment mechanic for a large construction contractor, so I have a good knowledge of electrical systems(DC and AC with generator sets). Iowa is a very large wind energy state but obviously wind is not a great supplier for residential homes. I've recently become fascinated with solar energy so I'm using this site to learn as much as I can. I have been trying to determine the net metering law in the state and ran into this article:

Iowa's statutes do not explicitly authorize the Iowa Utilities Board (IUB) to mandate net metering, but this authority is implicit through the board's enforcement of PURPA and Iowa Code § 476.41 et seq. Iowa's net-metering subrule, adopted by the IUB in July 1984, applies to customers that generate electricity using alternate energy production facilities (AEPs). Net metering is available to all customer classes of Iowa's two investor-owned utilities -- MidAmerican Energy and Interstate Power and Light (IPL).

There is no explicit limit on either the size of a net-metered system or on total enrollment in the IUB's subrule. However, separate rule waivers have allowed MidAmerican Energy and IPL to limit individual systems to 500 kilowatts (kW). Although Iowa's net-metering subrule requires utilities to purchase customers' net excess generation (NEG) at the utility's avoided-cost rate, subsequent rule waivers allow MidAmerican Energy and IPL customers to carry NEG forward for use in future months as a kilowatt-hour (kWh) credit. The net metering kWh offset effectively provides a credit at the customer's retail electricity rate. A detailed description of the Iowa net metering policy background is available here.

Am I reading this correctly that If I produced over 500 kw's a month that it would credit(bank) to the next month until production is low enough to use the bank up? I'm sure you all know way more about this than me so I appreciate any help you can give me! Thanks so much.

[Ian S]

Hey everyone. First off I'd like to say that I'm extremely happy to have found this site, vast wealth of information here! I'm a heavy equipment mechanic for a large construction contractor, so I have a good knowledge of electrical systems(DC and AC with generator sets). Iowa is a very large wind energy state but obviously wind is not a great supplier for residential homes. I've recently become fascinated with solar energy so I'm using this site to learn as much as I can. I have been trying to determine the net metering law in the state and ran into this article:

Iowa's statutes do not explicitly authorize the Iowa Utilities Board (IUB) to mandate net metering, but this authority is implicit through the board's enforcement of PURPA and Iowa Code § 476.41 et seq. Iowa's net-metering subrule, adopted by the IUB in July 1984, applies to customers that generate electricity using alternate energy production facilities (AEPs). Net metering is available to all customer classes of Iowa's two investor-owned utilities -- MidAmerican Energy and Interstate Power and Light (IPL).

There is no explicit limit on either the size of a net-metered system or on total enrollment in the IUB's subrule. However, separate rule waivers have allowed MidAmerican Energy and IPL to limit individual systems to 500 kilowatts (kW). Although Iowa's net-metering subrule requires utilities to purchase customers' net excess generation (NEG) at the utility's avoided-cost rate, subsequent rule waivers allow MidAmerican Energy and IPL customers to carry NEG forward for use in future months as a kilowatt-hour (kWh) credit. The net metering kWh offset effectively provides a credit at the customer's retail electricity rate. A detailed description of the Iowa net metering policy background is available here.

Am I reading this correctly that If I produced over 500 kw's a month that it would credit(bank) to the next month until production is low enough to use the bank up? I'm sure you all know way more about this than me so I appreciate any help you can give me! Thanks so much.

Yes, that is essentially how net metering works: excess produced one month carries forward as a kWh for kWh credit. That said, in many cases, you can't carry forward indefinitely e.g. here in Arizona, there is a zeroing out at the end of the calendar year where any excess at that point is paid off at pretty much an avoided cost rate. The resulting $$ go as a monetary credit on your next bill. It all then starts over for the next year. It can also get complicated if you have multiple tiers for electric use and/or time of use plans. PV will usually only work financially if you have two or more of the following:

1. Large cash rebates/tax incentives.
2. High electricity rates
3. High solar insolation
4. Net metering

There are other factors too so you really have to do a full analysis in an effort to see whether it will work for your particular situation.

[Sunking]

Not sure about Iowa but most states you forfeit those credits if not used in a specified time period typically 12 months. So the last thing you would want to do is over size the system. Otherwise you are giving money away.

[Cummins06TD]

Sunking- That's exactly what I was trying to determine on exactly what that legal mumble jumble was. I in no way a legal expert so was trying to figure out their wording. I guess the best thing I could do was call the electric provider, which is MidAmerican, and determine how they do it exactly. If they pay retail kwh back up to 500kw a month and after that is there avoided cost rate. Thanks again.

Ian- Thanks for the reply! to answer your ?'s
1. The electric provider offers no rebate so it's the fed 30% and 15% from the state of Iowa
2. Electricity rates are very low now compared to what I've been reading on other posts Summer rates are right at .08Kwh and winter rates are at .07KWH. My usage is right at 1,000 kwh in the summer and between 1,500-2,000kwh in the winter(Hot tub) The hot tub is no longer in service as my wife is pregnant so she never uses it and I never seem to have time so winter usage will be down significantly to around 500-700 kwh(which was usage before hot tub in winter)
3. Iowa isn't a great solar insolation state. Think I saw avg was 4.
4. Will try to determine this for sure.

The low kwh rate makes me lean towards it'd never be beneficial to me. but I'll still do the math and determine if I can make it work. I would buy a system and install it myself short of the electrical into the grid(have a licensed electrician in the family).

[Sunking]

Sunking- That's exactly what I was trying to determine on exactly what that legal mumble jumble was. I in no way a legal expert so was trying to figure out their wording. I guess the best thing I could do was call the electric provider, which is MidAmerican, and determine how they do it exactly.

Yes Sir that is what smart money would do is get the exact right answer.

[Ian S]

I would buy a system and install it myself short of the electrical into the grid(have a licensed electrician in the family).

My comments were predicated on someone paying for a turn-key operation. If you have the in-family capability with a licensed electrician to make sure everything is done properly to code, then it may indeed work for you in spite of your low electricity rates and mediocre insolation. You can check on the PVWatts website to get a better idea for insolation where you live.

[Cummins06TD]

Yes Sir that is what smart money would do is get the exact right answer.

Okay after some digging on their website I finally found a FAQ on net metering and found this
Q. Can a customer have a renewable generator that is over 500 kilowatts (kW) and net meter up to 500 kilowatts (kW)?
A. Yes. Any generation output over 500 kilowatts (kW) is not eligible for net billing, however, generation up to 500 kilowatts (kW) will be determined based on the ratio of 500 kilowatts (kW) to the nameplate rating of the generator. For example, if the nameplate rating of the generator is 1,000 kilowatts (kW), net billing will be applied to 500/1000 or ½ of the energy delivered to MidAmerican and the other ½ will be treated as energy being delivered under the Qualifying Facility rate.

Am I reading this right that if I was to install say a 5Kw solar array system that every KWH produced would be rated at same amount as what I pay? The bank also never expires, continues to add and subtract on plus/minus months. That would be beneficial to me if I would have plus months in the spring/fall to offset the lower power production in the winter.

[russ]

My comments were predicated on someone paying for a turn-key operation. If you have the in-family capability with a licensed electrician to make sure everything is done properly to code, then it may indeed work for you in spite of your low electricity rates and mediocre insolation. You can check on the PVWatts website to get a better idea for insolation where you live.

When his power rate is 7 to 8 cents/kWh?

[Cummins06TD]

When his power rate is 7 to 8 cents/kWh?

I forgot to include in the original post that they already notified us that over the next 3 or 4 years the rate will almost double. Gotta pay for that 8 billion dollars worth of wind farms somehow.

[Sunking]

You still have not answered the million $ ?

Do the credits expire? If so when and what do they pay for excess?

Here is what I see you trying to do. Game the system and trying to make a profit from my money. Not happy about that.

Here is the abuse I see coming. A typical house uses 30 Kwh per day. A 500 Kw system in Iowa produces on average 1600 Kwh per day or roughly 50 times more than you would use. So want to use my money to fill your pockets. That is why there are limits set to prevent abuse.

A 500 Kw system is what a Walmart store installs, not a home owner. A typical home Grid Tied system is 4 to 6 Kw

[Cummins06TD]

Am I reading this right that if I was to install say a 5Kw solar array system that every KWH produced would be rated at same amount as what I pay? The bank also never expires, continues to add and subtract on plus/minus months. That would be beneficial to me if I would have plus months in the spring/fall to offset the lower power production in the winter.

Sunking- the credit does not expire and i'm not at all trying to install a 500kw system. I was thinking enough to just power the home in the summer months and put it close in the winter. I'm not trying to rob your tax money, Do you think I'm happy about the fact that I personally pay around 30k in taxes a year plus what my wife puts in? And then single moms go around having 14 kids by 14 dads and guess what... yep we have to pay for them until there 18. I know where your coming from. But if the federal tax credit is there for people to use then why should I not? Say I got 4k federal credit on my system. My 20k in federal taxes every year more than makes up the difference and then some. So you can't see me gaming the system at all, my question about net metering was so the electric company wasn't gaming me by paying me .02 a kwh when i'm paying them .08kwh when I had money invested in a system to help live more energy aware. I have changed all light bulbs in my house to LED's and use the programmable thermostat all seasons of the year.

[Ian S]

Am I reading this right that if I was to install say a 5Kw solar array system that every KWH produced would be rated at same amount as what I pay? The bank also never expires, continues to add and subtract on plus/minus months. That would be beneficial to me if I would have plus months in the spring/fall to offset the lower power production in the winter.

That would appear to be how it works i.e the normal sort of net metering. Be aware that if you oversize your system, since the banked credits never expire, you may wind up adding to it indefinitely and never benefit from the banked credits you don't use. The key to getting the most bang for your buck is to properly size your system so that you use up your banked credits every year - or at least come close. What you need to do is get a monthly electricity consumption analysis for a couple of years. Use PVWatts to get a good idea of how much electricity you'll generate each month of the year for a particular size of system - you may want to use a less conservative derate factor of between 0.80 and 0.85 in their calculation. Play with the numbers to minimize annual over-production. This may also depend on actually when your system starts up.

Above all, don't let anyone make you feel guilty for making use of tax credits! They are there for a purpose and no different from any other tax break that's available.

[Ian S]

When his power rate is 7 to 8 cents/kWh?

With a 30% federal tax credit and a 15% state tax credit and doing the install himself, I'd say he has a chance. Pretty much a certainty if his rates double as projected.

[SunEagle]

With a 30% federal tax credit and a 15% state tax credit and doing the install himself, I'd say he has a chance. Pretty much a certainty if his rates double as projected.

I would say that there wasn't a single US Electric Utility that would be "doubling" their rates in the near future. Sure 5% to 10% increase but not 200%.

Now maybe in those areas that generate most of the electricity using coal, there is a chance of major rate increases. That would be due to either shutting down old facilities or having to install very expensive scrubbers in existing. But even with those changes the Utilities will never be allowed to double their rates. They have to get permission from a review board first even to raise the rates.

[Ian S]

I would say that there wasn't a single US Electric Utility that would be "doubling" their rates in the near future. Sure 5% to 10% increase but not 200%.

Now maybe in those areas that generate most of the electricity using coal, there is a chance of major rate increases. That would be due to either shutting down old facilities or having to install very expensive scrubbers in existing. But even with those changes the Utilities will never be allowed to double their rates. They have to get permission from a review board first even to raise the rates.

I'm going by this.