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Journal entries:   June 4 to July 27, 2007

Monday, June 4

Upon arrival, I met with Richard and Steve for a broad introduction and a short list of goals for the upcoming week.  

Here's how Richard and Steve described the goal of the summer's work :  

We hope to take advantage of the methane being produced (and currently vented) from the Blacksburg landfill to produce electricity.   Some of that electricity would be used in the buildings near the landfill.   But we also wanted to pursue a practical test to see how easy (or difficult) it would be to sell some electricity to the grid.   This would enable us to put into practice some of the work our colleagues have done in conceptualizing the use of distributed generation facilities to produce power for the grid.   Such a use contrasts the use of DG only for islanded (or isolated) facilities, which seems like an easier approach.   Therefore, my work will focus on 1) identifying equipment that can burn the methane produced by the landfill and generate electricity; and 2) locating the equipment that allows us to put that electricity on the grid.   The second phase of the work will require me to contact the local utility (Appalachian Power--a part of American Electric Power) to see what rules and regulations must be met for making the interconnection.

Tuesday, June 5          

I came to the office in the morning and began reading Steve's "Distributed Generation" folder of relevant materials.   I read generally about Landfill Gas (LFG)-to-energy projects and started work on the LFG Handbook .   Put together by the Environmental Protection Agency (EPA) in September 1996, the handbook was designed to be used by those involved with the agency's Landfill Methane Outreach Program (LMOP).   The LFG Handbook is a longwinded document, but it may prove useful as I learn about how to use LFG to generate power.

Wednesday, June 6

I read where I had left off in the LFG Handbook , making sure to write down anything of use.   I also noted important sources for the future as well as page numbers to find more relevant information.

Thursday, June 7

I again read where I left off in the LFG Handbook , again writing down any particular piece of information that I think will be important to the project.   The appendices are rich with cost estimation examples and tables, so a lot of my time was spent trying to figure out the method of cost estimation as well as thinking how it all applied to the landfill in Montgomery County.   It will be important to be able to recreate these cost estimations with this particular project.

Friday, June 8

I reviewed the appendices of the LFG Handbook again to gain a better grasp on what I was looking at and then moved on to the grid interconnection handbook.   I do not have much prior experience with such interconnections, and so the reading went slowly, even though the notebook is not particularly long.   I want to read it again to solidify my basic understanding of the material.

Monday, June 11

Today, I finally could visualize the project.   Steve, Richard, and I actually visited the landfill site.   We saw how the site currently uses pipes to vent methane gas from the landfill into the atmosphere.   Gas from one pipe, however, was burned.   The heat was also vented and did no useful work, but the landfill director pointed out that burning the gas is better for the environment than venting it.   Methane gas apparently is 25 times more potent as a greenhouse gas than is carbon dioxide.  

The visit also helped me get an understanding for the use of power by the waste management facility.   After the visit, I did a search for internal combustion (IC) generators and microturbines.   At the end of the day, I had explored the Capstone 30 kW microturbine, which also apparently came with an interconnection package that would easily allow us to hook up to the grid.   Good progress appeared to be made today!

Tuesday, June 12

I spent most of the morning looking up generators online and trying to find a generator that was rated specifically for landfill gas.   I was relatively unsuccessful in this search.   However, I explored the thought of centrifuging or treating the landfill gas to increase its methane concentration.   I also tried to further understand what was needed for interconnection purposes to the grid.  

Monday, June 18

After a break of a few days, I spent today searching for a method of separating CO2 and CH3 for purposes of boosting the influent methane levels in the gas.   I think that if there is an economical method   for removing CO2 and siloxanes, then it will improve the performance of any generator that is put in place at the landfill.   Siloxanes are silicon based particles that derive from the decomposition of cosmetics in landfills.   They are inert compounds used as filler for these products and do not readily break down.   Unfortunately, these compounds are notorious for fouling engines and piping, and so a gas treatment system is necessary to avoid constant maintenance and fouled generator components.   I also started to look for any information available online referring to the hardware requirements of connecting to the power grid.

Wednesday, June 20

I searched online for more economical methods to separate gas at the molecular level, but I am having difficulty finding something commercially available that can help up meet our objectives.   I also looked for more IC engines after deciding that this was the direction this project was taking.   It appears we may not be able to use the microturbine because its output and energy efficiency are quite low.   The microturbine also requires cleaner gas than IC engines; the siloxanes present in the landfill gas foul the microturbine quickly, meaning higher maintenance.    This discovery is somewhat of a disappointment.   With Capstone's Direct2Grid attachment, the micro turbine can be plugged in directly to the grid without any additional equipment.   It couldn't be easier!   But if the turbine won't meet our needs, we need to know how to interconnect without the "plug-and-play" attachment.  

Thursday, June 21

I have decided to stop looking for air separation methods and focus more on finding IC generators.   By the end of the day, I found two IC generators that I think have promise, in addition to the Ford generator located earlier by Steve.   I talked briefly with an electrical engineer friend about the hardware requirements, and he informed me that I first needed to know what the generator stats are (i.e., frequency), as well as what voltages and how many phases are going to be coming off the generator.

Friday, June 22

I learned from online research about a synchroscope, which is a tool (costing about $600-$800) that helps to synchronize the frequency of electricity produced from the generator with the frequency already in the power grid.   I went back to familiarize myself with the generator statistics of the three IC generators that I had found to try to better understand what type of power they produce.  

 

Monday, June 25

Today I re-reviewed Steve's grid interconnection notes.   I also set a meeting time with Tim Thacker tomorrow, and I began to collect the information I needed in anticipation of the meeting.   Tim is a PhD student working in the Electrical Engineering department at Virginia Tech and has already done some research on various types of distributed generation.   I feel that it is important for me to communicate with Tim, and I hope that he will be able to fill in the missing pieces of the puzzle.   I continued to look for any additional hardware requirements online, but I hope that Tim will be able to help me more than the Internet has so far.

Tuesday, June 26

Today's meeting with Tim was a great help.   I learned a lot about AC-DC-phase controlled AC converters, which is what we need to connect our generator to the power grid.   It seems that if we can match the frequency/voltage and phase angle with that of the grid, we should have no problem connecting our DG unit.

Wednesday, June 27

In a discussion with Steve, I reviewed what I had learned, and we decided to continue looking for generators that have a built-in interconnection capability.   I also looked online for AC-AC phase controlled converters.   I found one AC converter that I really liked, but I can't find any indication of cost.   I will look into this more later.   I contacted the generator companies asking them about any kind of built-in converters any of the generators have.

Thursday, June 28

I got a response for the Ford generator saying that the generator has a voltage regulator, but I am unsure if this is what I need.   After looking up voltage regulators and what they do, I do not think it is what we need for the project.   I have yet to get any response from the other generator companies.   Steve and I discussed the future of the project and refined our objectives.   It seems that it is now important to first find a generator that we can commit to buying and go with it from there.   I am finding this project exciting and can't wait to get my hands on a generator.

Friday, June 29

I performed research on siloxane filters and tried to get an idea of how difficult it would be to filter out contaminants in the landfill gas that may cause fouling in the IC engine.   Although I don't see that filtering siloxanes is going to be as important for the goals of this project, I think it is important to know and understand for treating and using biogas in any application.   I spent most of the day educating myself about siloxane compounds and how they can be removed.

Monday, July 2

I returned to the generator search, spending most of the day disappointed.   I am having a great deal of trouble finding generators online that meet the requirements of the project.   I have found three, but I don't see that any are exactly what we are looking for.   We are looking for a generator that can be run continuously at a constant output.   Unfortunately, the smaller generators that we are looking at for this project are designed as backup generators and only designed for brief, periodic power generation.   There are larger generators made my Caterpillar and Waukesha that have been tuned to be powered with landfill gas, but these generators are much too large for the application we are considering.   We also need power generators that meet the phase output required to connect to the grid.   There are plenty of generators designed to run a home or small business, but it is difficult to find a generator capable of putting power back onto the power grid with such high voltage.  

I think we may have to buy the most economically feasible generator and then buy an AC-to-phase controlled AC converter for the generator.   This particular piece of hardware is important because it helps protect the electricity on the grid and will condition the electricity coming from the generator so that it matches the electricity already running through the grid.   I also don't know if a three phase or single phase generator is what we need for this project.   I think that the make-before-break idea is much more relevant for our project.   Make-before-break is a concept in which the power generator is set up independently from the grid and produces power just for use on landfill facilities.   If the power were to go out on the main power grid, the make-before-break switch can ensure that the generator is not putting any electricity out on the main power grid.   It is a safety feature that might protect any AEP employees from being electrocuted while trying to repair downed power lines.

Tuesday, July 3

I spoke with a sales rep about the Ford generator, which I believe is the best fit for our application, to see if it is possible to control the phase angle of the electricity generated.   I believe that the Ford generators are the best fit for use because they meet most of the requirements we have for the interconnection.   It is the only generator that is capable of being run continuously for extended periods of time.   It also offers a three phase connection with voltage regulation.   Unfortunately the Ford representative did not know how to answer my question about interconnection, which led me (again) to believe that it will be necessary to get an AC-phase controlled AC converter for our project, if hooking up to the grid is what we want to do.   I also requested quotes from a manufacturer for the converters.

Wednesday, July 4

I took most of the day off but spent some time looking for the differences between the Ford model 01738 and the 01735.   I think the 01735 will meet our needs well because it offers us the most economically-friendly machine.   The 1738 model Ford generator is a larger 85 kW generator while the 1735 is a 50 kW generator.   The difference in price for these two generators is minimal and so choosing the larger of the two will not greatly affect capital costs and will allow more power to be generated for our project.   The only reason to pursue the smaller engine is if it were easier to understand and maintain.

Thursday, July 5

I emailed the manufacturer to get a better idea of the differences between the two Ford generators.   I also like the Guardian Elite 100 kW generator, partly because it comes with electrical controls that were the most compatible with grid interconnection requirements.   However, it is designed to run only for short periods of time and will not sustain the 24/7 power needs of the solid waste authority.   The generator was designed as a stand by generator and not as a power supply generator, so that it could only be run for short periods of time as a back up generator and not as a full-time power source.   We may need to keep looking.

Friday, July 6

I spent most of the day on the phone with sales representatives for each of the three main generator companies trying to determine their machines' capabilities and ability to be hooked up to the main power grid.   It seemed to be a pointless and frustrating venture because the reps couldn't answer any of my questions.   It is important for me to know if the generators are able to be interconnected with the power grid and what controls come with the generator.   I also just want to find some document that explains what grid interconnection entails because so far I still feel in the dark on the matter and have not been able to get any information from the people and companies that should be able to provide this information.   I am not sure if it is because I am not asking the right questions or if they just don't know the answers, but I feel like making any progress is slow.   I am having a hard time with the electrical engineering side of the project.   I feel like the more I learn, the more complicated I realize grid connections are.   However, it is difficult to me to comprehend why the generator companies have not developed an easy way to make their generators capable of connecting to the main power grid.   They manufacture these generators in single and three phase modes, and if they manufacture a three phase model of the generator, then why is it not made to be grid-ready?

Monday, July 9

I searched again online for AC-to-AC converters and contacted a few companies asking about their products and prices.   One particular company, Applied Power Systems, Inc., seems to show the most promise for our project and hopefully makes the converter we are seeking.   I continued my search for converters, but it seems to be an uncommon product, and I am finding that not many companies manufacture such products.   I feel that every day some different obstacle stands in my way making it difficult to get any information that might shed light on power generation and connecting to the power grid.  

Tuesday, July 10

I heard back from Applied Power Systems.   The rep suggested rectifying the output of the generator and then inverting the DC to synchronized AC at a slightly higher voltage than the grid to force current back onto the line.   This current will match the phase of the electricity on the grid and will also allow the electricity to flow easily onto the power grid.   Just as water flows downhill, electricity flows from higher potential (voltage) to lower potential.   The company seems to be helpful and forthcoming.   Although it does not offer the product we need, it helped set me in the right direction.   I appreciated the quick response and willingness to help.   I will keep this company in the back of my mind while I try to narrow my search.   I also contacted AEP,w trying to learn more about the specific power specifications for the electricity running through the power lines in the Blacksburg/Christiansburg area.   Finally, I began to look at and try to understand inverters.   There is a lot of information online about inverters, especially those that connect solar (photovoltaic) power to the power grid.   I hope my studies of these inverters will prove useful to our project.

Wednesday, July 11

I was surprised to see an email from AEP upon arrival at work.   It seems that AEP is the most willing to help and is very forthcoming with information about the power in the grid, and I hope that the company will help further in the future.   I also expressed my frustrations with the research to Steve, and he proposed that we purchase a generator now and spend time learning how it works on our own.   I agree that some hands-on learning would be very beneficial and I think that playing with the generator would not only allow me to learn what I need to know about the generator, but also take me away from the frustration of doing online research.   Unfortunately, it is difficult to select the appropriate generator and the power generation goals of the project seem to change almost daily.   We also discussed a potential project and funding opportunities at the Virginia Tech landfill.   The landfill is much smaller than the county facility, but perhaps we can obtain some funding.   Steve has visited the landfill, and I hope to do the same in the near future.  

Thursday, July 12

I spent a lot of time today searching online today for any information about various DG systems and how those systems are connected to the main power grid.   I don't think that actually generating electricity or running landfill gas through a natural gas generator will be the challenge in this kind of project.   The real challenge comes with connecting to the power grid.   I have yet to determine exactly what hardware is necessary to connect the electricity generated to the power grid, and what is necessary for net metering to be successful.   Unfortunately, most of the information available online deals with photovoltaic power, which is generated in DC at a constant rate and then inverted to the proper AC current, making it difficult to relate to IC generators.   The closest I could find relevant to IC generators, with the exception of the Capstone micro turbines, is wind power, and I think that researching wind power generation and how it interconnects to the grid will help me see how to do the same with IC generators.

Friday, July 13

I again searched online for clues about interconnection hardware.   I find it unbelievable that the information needed to connect to the power grid is not more readily available online, considering that it is currently being done by a few companies in the United States.   I realize today that whatever hardware is necessary for interconnection to the power grid needs to include a converter as well as a number of safely devices that will be required by the IEEE 1547 standard (currently being crafted).   I sent an email in vain to Capstone asking about their Direct2Grid unit that connects to their microturbines, apparently making them "grid ready."   I don't expect too much of a response from them, but I was able to find a discussion about the unit that briefly describes it as nothing more than an inverter ( http://www.distributedenergy.com/de_0411_microturbines.html ).  

Monday, July 16

Steve and I met to discuss the possibility of establishing a demonstration site at the Virginia Tech landfill.   (This is a smaller landfill than the Montgomery County landfill.)   We are now thinking about using a low power generator (maybe 15 kW) as a way to expand our knowledge on net metering, interconnection, and landfill gas use.   The newly formulated idea gives me a bit of optimism about the project, and I hope that we will find success eventually, even though it seems our time this summer is running short.   I started looking for flow meters online and found a few websites fairly quickly.   However, I did have some trouble finding flow meters large enough to fit into the gas vent at the VT landfill.   I also looked at some smaller generators online and found a few.   However, the price for the smaller generators is not significantly less than the larger ones, so I think the most economical decision is to find one that generates about 50 kW.   I also wonder if it would be a good idea to just purchase a Capstone microturbine for the time being, and then learn about the specifics of interconnection from using the Direct2Grid unit that comes with it.

Tuesday, July 17

I continued my search for 4" flow meters online, emailing each company for a quote on its product.   Steve and I also took a trip out to the VT landfill so that I could visualize the site and think about how to proceed.   We would need to install a flow meter in the exhaust pipe where a blower actively discharges the gas into the air.   Next, we need to adjust the blower speed to slow down the flow rate of gas in the exhaust system.   With the current high flow rate, the methane level of the exhaust is very low--so low that it could not be smelled.   However, if the flow rate can be altered in the blower, and a lower flow rate achieved, the methane concentration would rise, and an optimum setting on the blowers could be reached.   Doing this, we would take gas samples to find the optimum methane level with the best flow rate.   With this information, we may be able to set up a demonstration project.   Today I was also given a small Honda EU 2000i generator with an inverter.   I briefly took the unit apart so that I could see how it was connected, which was a beneficial experience.   But the small single phase generator cannot relate well to the larger three phase generators we will need for DG projects.

Wednesday, July 18

I am now getting frustrated because I haven't heard back from anyone concering the Capstone Direct2Grid technology or the 4" flow meters I had inquired about earlier.   To me, it seems the next step is to assess the feasibility of using the VT landfill as a demonstration, but work needs to be done to prepare the site and understand the gas characteristics coming from the landfill.   I also spent time searching online for any more clues about connecting to the grid.   I find it almost unbelievable that there are no companies advertising/selling a grid-connect kit because I know it is a technology being used currently, even if only by a few companies.

Thursday, July 19

I still haven't heard anything back from a flow meter vendor, and I find that very frustrating.   With the exception of asking Capstone for some detailed insight to their technology, this is the longest it has taken a company to return my email.   I spent time writing emails to AEP again today, asking about the company's grid interconnection protocol, and if it had a detailed list of requirements for grid interconnection.   I also asked the rep to send me some kind of schematic that might explain or show the hardware we need in order to connect to their power grid.   I hope the company continues to be cooperative instead of withholding information, which seems to be happening with other companies.   AEP provides a publication that provides a step by step guide to grid interconnection.   (One must request this guide from AEP.   Some information is available at https://www.appalachianpower.com/global/utilities/pdf/InterconnectionBrochure.pdf and by writing a note to dgcoordinator@aep.com .)   I consider myself a reasonable competent engineer; however, I had a great deal of difficulty understanding the terminology of the document.  

I have a feeling that whatever technology is needed for DG and grid interconnection is a closely guarded secret, and it seems as though much more work lies ahead of us to understand this project.   It is frustrating for me at this point to feel so unsuccessful.   Although the process is conceptually simple, the information required to plan and carry out the project is much more difficult to obtain and use.   It seems as though every step forward taken to understanding the process, two steps are taken back and more challenges arise unexpectedly .

Monday, July 23

I spent the morning searching for all safety devices required for a grid connection (excluding the AC-to-phase-controlled-AC converter that we know is necessary [from our discussions with Tim Thacker] for conditioning of the electricity produced before it is put on the AEP power grid).   I compiled the following list:

•  Interrupting device

•  Interconnection disconnect device

•  Generator disconnect device

•  Over voltage trip

•  Under voltage trip

•  Over/under frequency trip

•  Automatic synchronizing check

I do not have much of an idea of what these things are, but they seem to make sense.   I am going to try to map out all of the hardware requirements so that it is possible for me to visualize.   I also met with Richard and expressed my frustrations with the slow learning process and how difficult this project actually is, as opposed to its fairly simple-to-understand concept.

Tuesday, July 24

I spent my day writing down in more detail my frustrations and how the project has gone over the past few weeks.  

Wednesday, July 25

I finished catching up with my journal entries and adding the thoughts I had throughout the summer.   I showed Steve some information I had found about air filtering and removal of siloxanes as well as other contaminates in landfill gas.   I continued my search for the items I know are necessary and emailed Tim Thacker about the items, asking him to suggest alternative names to find these products.   I also discussed with Steve in detail the future of this project including the potential for funding.   However, it is clear that a great deal more work needs to be done for a demonstration of this DG source.   Even with a lot of additional funding, this project will remain a difficult one.

Thursday, July 26

Today's work was quite successful.   Steve and I discussed putting together a price list for the equipment that might be needed for a project for the VT landfill, but we also considered known equipment requirements at the Montgomery County Landfill.   I assembled a list for the generator, gas treatment, a flow meter, and searched for a portable FID (flame ionization detector).   Unfortunately, I was not able to find a FID unit with the capability to read 500,000 ppm methane or a gas stream that is 50% methane.   I also got the contact information for the EPA Landfill Methane Outreach Program ( LMOP) representative for Virginia and will try to get in touch with her.   I realize that if we can communicate with the LMOP rep, we might be able to get in touch with a landfill in our region that is already interconnected with the grid.   If we were able to find this, I am sure it would bring a great deal of insight to our project.   We need to decode the great secret that is kept so well in the field .

Friday, July 27

I spent my time today getting in touch with people to complete my price list.   I found everything I need except for the FID, and I was unable to contact the LMOP representative because she was on vacation.   I will continue to pursue contact with her because I truly think that finding the answer to my questions lies with her.   I also realized that the gas treatment system that we are looking at could cost as much as $500,000, a price that could cripple our ability to successfully complete a project converting landfill gas to energy.