Permitting process for Cogeneration facility

[gokulkrish2]

Hi fellas,

We are in the process for investigating a feasibility of a cogeneration facility.

The process is a Sulphuric acid production plant which gives us a lot of heat, which in turn we intend to convert to steam and produce power.

In relation to this i have a lot of questions.

We are to produce about 20MW of power.

Our load at Mine site including the power plant load goes more than 40 MW and so we can use all the power we produce. But in the event we have to shut down our main loads (RECTIFER LOAD approx 30MW) there is a possibility that we will have to wheel power in to the utility.

I know we can shut down the acid plant or can dump the steam. But there are other constraints and to keep it short lets just assume that we can not do both.

Now my questions are:

can we send this power on the utility transmission line to a different mine site about 100 miles from ours??

Is permitting required for this by law and if yes what are they??

Also, i have this doubt. As we generate and our mine load is close, in all practical real world we assume what we generate is going to be consumed by our closest load Ie our mine site. But how can we guarantee this?? There is a chance that the power can back flow to the utility line correct? In that event what to do?? I know we can monitor reverse power flow and trip the generator but is that the only option. What if this keeps on happening.

Is there a way we can control power and say it has to go only to our loads?? (I know it sounds crazy but just wanted to ask the experts. u never knw... it just might be possible)

In general what are the things i should take care of in the event we happen to power producer from jus being a power consumer.

Forgive me if these are all novice questions. I have little knowledge on transmission and barely getting involved in it because of this co generation facility.

Thanks in advance

gokul

 

[dpc]

Assuming you are in the USA: If the power is being sent on a transmission line, as defined by FERC, you are allowed to wheel the power from one site to the other. However, a wheeling charge must be paid to all utilities involved. This is all mandated and regulated by the Federal government. Appropriate metering at each end would be required.

Depending on the region of the country, you would need to file an application to use transmission capacity with the local regulating authority. You would also have to pay for system feasibility studies, system impact studies, and any necessary design and construction related to the transmission system. The waiting line for these types of projects can be quite long in some parts of the country.

As far as the actual power flow, it will go where it goes. The balancing authority will make the necessary accounting entries based on the metering at each end and send you a bill or maybe even a check if you are lucky.





David Castor

http://www.cvoes.com

 

[dpc]

And if the plant is NOT in the US, ignore my previous message.

 

[davidbeach]

1. You need to talk to your utility; interconnection requirement vary tremendously.

2. You need to hire a consultant familiar with interconnecting generators with that utility.

The best you can do here are some very general answers that may or may not be applicable.

If you do export power from one site, it is just added to the total mix, what you might then import at another site could be coming from somewhere else entirely. For instance if the general power flow on the grid is from north to south and your generation export is south of your import site, none of the power produced by your generation will make it to your other site. But power wheeling contracts completely ignore that and work on the fiction that you can insert power at one location on the grid and extract that same power elsewhere.

 

[gokulkrish2]

Hi DPC and davidbeach,

Thank you both for the reply and here is wat i have more to say.

I am in the USA and this facility of ours is in Arizona.

I went online to the westerns transmission interconnection website and saw the contact for the transmission line which we would be using.

I will contact them and have them help me more.

I understand we need to pay to them, but its this part which confuses me more. As i mentioned before, we will be sending out power only when we shutdown some of our process for scheduled maintenance purposes.

Now, if in a contract we say we want to wheel 10MW of power every week for 2 days, arent we binded to provide it anyways. But we sometimes change maintenance and downdays. What can we do in that case.

Also, what about the other question. Is there a way we can make sure what we generate is used by us first? Our site load is the closest but they are very heavy loads of large impedance. we have a town nearby which is where i doubt could be a significant next load area. Please advice.

 

[dpc]

The transmission provider is simply providing you with transmission capacity. You are selling the power to yourself.

To get capacity that is available whenever you want it, there will probably be some type of capacity charge, even if you never export any power. In addition, there will be a wheeling charge based (I believe) mainly on the actual power exported.

As for your last question - no. One plant is putting power in at one point and the other plant is using power at another point. As far as where the power comes from and where it goes, this is just complicated bookkeeping.

Let's say one of your plants is exporting power while the other plant happens to be shutdown? Unless you have a contract with some other entity to purchase that power, you are essentially donating it for the good of the order. The transmission provider generally does not buy your power. And if they do, it handled by a completely separate group.


David Castor

http://www.cvoes.com

 

[rcw retired EE]

I assume your plants are presently buying power from a local utility. That is where you need to start to find out their requirements for attaching generation to their system. That data is probably on a website.

Your company will have to file an application with the utility and pay for the utility to analyze their system to determine the impact of the new generation. There probably is a waiting list of a few months since many companies are trying to put solar power and "green" power on line in that area.

Based on the results of the study, you may have to pay for system modifications needed to assure reliable operation when the new generator is on line. Your changes will not be allowed to negatively affect any other customers or the system reliability so equipment modifications may be needed.

Once that initial phase is complete, your company can start negotiations for selling the power to someone, most likely the serving utility. Since your 20 MW is intermittent and not dispatchable, its $/kW or $/kWh value is relatively low. It may not even pay for the installation.

As others have stated, don't get caught up in where the power goes. Just think of it as selling to the utility and buying it back at the other location. In Arizona, many "farmers" sell water to the large cities' water authorities. When a farmer's well pumps a gallon of water into the pipeline, he can't tell where it is going to end up or who is using it. Your kilowatts are exactly the same.

The best thing you can do now is hire an experienced consultant or a company to investigate the options and give you an idea of the costs before you waste time and money.

(I know a company).