PURPA - Net Metering

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Dark Knight

Silent Guardian
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Hey Enviro Engineers...

I am doing a research to implement Net Metering in the company I work now. Have found that this is mostly an environmental thing. Is any of you familiar with this PURPA Net Metering thing?

Let me know.

 
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Under the PURPA the utilities are required to purchase a certain amount of power from what are called Qualified Facilities (determined by FERC). These include renewable and cogeneration facilities. There are fairly strict requirements for being a qualified facility - under some circumstances a plant might be a renewable plant but not qualify as a QF. I think QFs are scheduled in a matter called "Net Scheduled" meaning simply that their Net output delivered to the grid is measured (metered). There are many ways that utilities do this, I think. Do you actually have to set up some sort of net metering system?

Portions of the PURPA act are also the basis for electricity deregulation in my state - where the utilities were required to divest in power plants and sell them to Exempt Wholesale Generators - such as Duke Energy, etc. This led to a complicated scheme involving generators, scheduling coordinators and traders (like Enron), and utilities and caused a lot of problems. Only recently have utilities been allowed back into the power generation business here in Cali.

 
BiO - After reading your descriptions of what's involved, I'm sorry to report that I have absolutely no clue and no experience with this stuff.
Neither do I. The "problem" is that I have to develop the plan for my company to implement it. It is going to be an interesting project. Darn....I should have stayed where I was. :joke: Two engineers here already declined the "honor" to be in charge of this. I had no option since I am the new guy.

I can only say... :bio: If I passed the fudging test I can do this....yesssss.... :bio:

 
^ If you saw my latest "I have to be an expert on this in 6 hours" thread I posted this morning regarding water treatment with ion exchange and subsequent treatment of the wasted process water, you know this happens to all of us way more often than we like.

Then again, if we didn't wanna be professionals who have to learn and apply new skills as needed, we woulda became cad drafters or rodmen.

 
^ If you saw my latest "I have to be an expert on this in 6 hours" thread I posted this morning regarding water treatment with ion exchange and subsequent treatment of the wasted process water, you know this happens to all of us way more often than we like.
Then again, if we didn't wanna be professionals who have to learn and apply new skills as needed, we woulda became cad drafters or rodmen.
AAAAAAAAAMMMMMMMEEEEN

 
Your company may have given you a great gift (although it doesn't seem like it now). Net metering, demand response, renewable porfolio standards - these are things of the future. If you are actually the responsible engineer in charge of a net metering system development for a fairly large utility or generator that is something that could translate into a very marketable thing on a resume. Most utilities out here have teams of people working on this stuff. I don't know if you operate under an ISO or other interconnect tariff, but you may want to check that out. NERC may also have some regulations - but I'm not sure they apply at the generation and distribution level. Well, I'm sure you'll figure all this out on your own. Good luck - should be interesting.

 
BIO --

You are probably tasked with this great item because the state you live in has mandated that RENEWABLE energy sources be included in the portfolio of expanded power generation projects.

The program is being implemeted out of the Florida Department of Environmental Protection. The office is called Florida Energy Office (FEO) :true: http://www.dep.state.fl.us/energy/ For myself, I know very little about what initiatives are being generated from this office. I only know that it is a 'big ticket' item for the Governor's Office.

I agree with Benbo - this is probably a nice chance to add something to your resume AND shine in your new job!

:bio:

JR

 
BIO --
You are probably tasked with this great item because the state you live in has mandated that RENEWABLE energy sources be included in the portfolio of expanded power generation projects.

The program is being implemeted out of the Florida Department of Environmental Protection. The office is called Florida Energy Office (FEO) :true: http://www.dep.state.fl.us/energy/ For myself, I know very little about what initiatives are being generated from this office. I only know that it is a 'big ticket' item for the Governor's Office.

I agree with Benbo - this is probably a nice chance to add something to your resume AND shine in your new job!

:bio:

JR
Thanks for the link JR...You are the man!!!!!!!! :plusone:

That will justify why EB should not and cannot be blocked from my computer... :17:

You will have an honorable mention in the presentation, if it makes all the way up to the Director here.

Benbo...thanks to you too for the advices. I now realize this is a big thing and it is a chance to make the difference. Funny thing is does not seems too hard to implement. IEEE already has design standards and IREC has models for Net Metering and the Interconnection rules.

It is a mumbo jumbo legal mess

:bio:

 
I don't think it is technically that difficult - as usual in regulated industries it is the legalities that make things messy.

 
Ouch! In an oddly related coincidence, the legal counsel for our Board of Professional Licensing is mostly experienced in utility law and especially renewable engery & green building stuff. He managed to get a law like this passed in our legislature over a year ago. I laughed my ass off. The first deadline is coming up in December, and I'll eat my shorts if anyone steps up wth an actual source of alternative energy by then.

But benbo and JR are right - this is a gift to you. Learn everything you can on it and stay ahead of everyone else in your company, and you will be golden!

 
Here's how I understand net metering. Disclaimer: these are my own views and have nothing whatsoever to do with my employer.

In the old days, if a utility allowed a small generator to connect to it's system (and it often had no obligation to do so), they often would use two separate meters. One meter would measure the energy used by the customer, and the other would measure the energy supplied by the customer to the grid. The energy used would be billed at the regular retail rate (say 9 cents/kwh). The energy supplied would be credited at a wholesale rate (perhaps 3 or 4 cents/kwh).

With the increased interest in alternative energy, many states have passed net metering laws (as far as I know this is on a state-by-state basis; there is no federal mandate (yet)). Under this system, the generator is credited at the retail rate for the energy delivered to the grid. This could be accomplished by using a single meter--it would run forwards for energy consumed and backwards for energy supplied--thus "net" metering. Technically it may not be that simple; I'm not familiar with what these installations actually look like.

I believe in most cases, net metering only applies to very small (usually residential) generators--like a few solar panels or a small wind generator. Usually the larger alternative energy projects are treated like a wholsale Independent Power Producer, but these IPPs often get special government incentives and/or a special contract with the utility.

Of course, there is a whole raft of other issues with connecting small generators to a distribution system. The most important in my mind is making sure the generator is disconnected from the system when there is a fault, to prevent injury or death to lineworkers. A larger generator could even cause power quality problems for other customers on the system, and even try to "island" load on the circuit if the circuit recloser trips or a line fuse blows. Many of these types of issues are addressed in the IEEE standard 1547 (a co-worker of mine was on the working group for this standard). Fixing these problems can sometimes add a propotionally large amount of cost to a small generator project. My emplyer had to come up with a standard interconnect process for these small generators a few years back. But these issues are separate from net metering itself.

That's about all I know about it. I'm a little surprised this is just being passed around to whoever wants it at your company, BIO. At my company this would be a big deal.

Now, for my own personal opinion on net metering (again, this is my opinion, not my employer's). I think it's a crock. Don't get me wrong; I think alternative energy sources are great. BUT, I think net metering is a cop-out for the politicians. They are forcing the utilities to buy power at inflated prices, and the utility is just going to pass that cost on to the other customers. In my mind, this is a veiled tax increase. If the politicians want to support alternative energy, they should have the balls to increase taxes and provide direct government subsidies--I think in the long run this would have a bigger and better impact.

 
FYI

If you are interested in Green Power and Renewables take a look. I am working on a project for my company and that web site was a great help.

I have to prepare a presentation and will try to post it here. Finally have all I need to do it. If I make a video presentation you will find my writing is way much better than my diction. It will be fun though.

Solar Initiative - DSIRE

 
^ If you saw my latest "I have to be an expert on this in 6 hours" thread I posted this morning regarding water treatment with ion exchange and subsequent treatment of the wasted process water, you know this happens to all of us way more often than we like.
Thread... what thread? Am I going crazy?

 
FYI
If you are interested in Green Power and Renewables take a look. I am working on a project for my company and that web site was a great help.

I have to prepare a presentation and will try to post it here. Finally have all I need to do it. If I make a video presentation you will find my writing is way much better than my diction. It will be fun though.

Solar Initiative - DSIRE
BIO

Glad you found this site! I know this thread is old, but I only saw it today. DSIRE has links to both federal and state agencies that let the small fry know if net metering is possible in their location. I have been looking into this issue lately because I have been thinking about generating electricity at home while I'm riding on the bicycle trainer. The weather is getting too cold and messy for me to ride outside.

Mudpuppy

I can appreciate your point of view as a taxpayer, but my conclusion thus far is that for the majority of small suppliers to the grid that use "net metering", the net flow is from the utility to the small supplier. Very few homeowners or small businesses can supply more power to the grid than what they use; at times this may not be true, but over the course of the year it is probably the case. A compromise would be that any net power supplied to the grid would be purchased at the prevailing wholesale rate.

For example, If I put a windmill or two in my yard, there are times when I might supply more to the grid than I the grid supplies to me, but over the course of the year, my net flow of electricity is from the grid to me. The windmills just reduce the amount I get from the grid.

 
^^^I agree with you.

The purpose of the net metering is to provide the costumers a way to generate their own power under the supervision of the utility. It is nothing else and it is not complicated. The meter reads what comes in and also what comes out and then the utility bills the costumers for the net comsumption.

What many companies are doing right now is giving the costumers credit for any power supplied to the grid, which happens on very rare cases. I had the privilege to see a PhotoVoltaic(PV) installation and the owner was kind enough to explain the subject in detail. He even gave me a copy of his bill and a graph showing his comsumption vs generation. It was very nice and big house and, I do not have the bill on hand right now, none of the monthly bills were higher than $150.00. You have to see the house to realize that for a place that big that is a low payment.

This issue about what to do with the power the costumers put into the grid has been a dealer killer in many places. The utilities refuse to pay the costumers for that power at the same rate since it costs more to the utility to deliver than it costs to the PV system owner. A credit seems to be a way to go, not because is perfect but because is less harmful to the utility.

It has to be clear that only in very rare cases the costumer's generation will be bigger than his use. Safety devices, interrupters, have to be installed even when it has been demonstrated that they are not necessary. There is a long way to go but I see this as a great alternative for the people to contribute to alleviate the energy crisis. Heck; I will install a PV system at home when I have the chance. It is not cheap by any means. But it worths the investment on the long run.

If any of you have had experiences with PV please share them here.

:bio:

Hey SS, nice to read you again my friend.

 
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Sorry if I'm opening a dead post... I am mgr. of engr. (dir. of engr after I get my PE and demand a 15% raise) anyhow,

we net meter our photovoltaic installations. Really simple, I've got a short contract put together by our attorney and the state PSC -can share it with you if you like. Net metering is easy as falling off a cuban refugee raft, the accounting dept may say different as they do have to read two "meters" and do some subtraction (yep, higher math to some).

 
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