10 replies to this topic

[David MacIsaac]

Hi,

I was interested in how ready the GEK Power Pallet is for continuous operation.  I am writing the business case for a loan to replace my two daily drivers with all electric cars and a GEK with CHP set-up built by myself for the house.  I would also get $1200 a month on a 20 year contract with the local power distribution network which should nicely cover the monthly payments for a loan to cover the total costs of setup. I see you had a 30 hour run over 4 days without to many hiccups.  What are your thoughts on the barriers between this and 24 / 7 / 365 operation?  I understand that there would be maintenance to the genhead, motor, and clean out tar buildup in the internals of the GEK but how long do you think this would go with a auger feed system with unlimited amount of well prepared feed stock.

On an additional note I may be in a position to secure practically unlimited amounts of feed stock, I work for a construction company as a health safety and environmental coordinator and through our several business units we do 3 billion dollars of work a year in Ontario Canada and most of the waste haulers locally have told me that they have to pay to dispose of construction lumber due to it being considered contaminated waste and the pit is so far out of town it is a major expense which most haulers loose money on.  One hauler has offered to drop off up to 100 tones a day to my 25 acre property just out side of the suburban sprawl of Toronto, 100 km closer that the pit they have to go to.  In the GEK community what do operators value their feed stock at?  I would also be interested in where GEK operators are finding the feed stock and how much time is associated with this if scavenged?  If purchased how much are you paying for this in tones?  

Thanks for the feedback,

David MacIsaac

[jimmason]

David MacIsaac said:

Hi,

I was interested in how ready the GEK Power Pallet is for continuous operation.  I am writing the business case for a loan to replace my two daily drivers with all electric cars and a GEK with CHP set-up built by myself for the house. I see you had a 30 hour run over 4 days without to many hiccups.  What are your thoughts on the barriers between this and 24 / 7 / 365 operation?

David MacIsaac

david, this is a very good question.  we're asking ourself the same thing, as are many others.  one of the most exciting current proposals is for using the power pallet for rural telcom towers in the dev world.  the uptime and and longevity needs for this application are very high.  we're currently exploring how realistically we can meet these requirements.  

we're going to be doing progressively longer and longer runs this summer.   there are certainly many more details and optimizations to work out.  having all the basics finally worked out as an integrated whole is deeply satisfying, but it does not end the process.  we need to keep learning and refining.  we'll be continuing this in the coming months.  given the modular architecture of the gek, and adjustability of all components, new learning and parts are always backward compatible, thus we can continue to bring older units up to current best spec.  


achieving longevity is an issue far more complicated than simply building things in stainless.  i know lots is being made of all stainless gasifiers.  i find this somewhat entertaining, as materials issues are about the easiest thing to solve in all this.  the difference between welding stainless and mild is different wire in the mig welder.  refractories are easily pourable into any form.  it is easy to alter the specific materials used to match the desired use scenario.  we default to a mixed mild and stainless build scenario because we find it to be the best value fit to typical use scenarios.

what is difficult to solve for real longevity (even if for just an honest day run) is the process control, automation and fuel feed issues.   the process control and automation issues needing solutions beyond the "it's works" demo video are somewhat daunting.  we've been sobered about all the details needing attention after the basics are all in order, but before you can really have long hands off automated runs without human attention.

gasifier gensets are in many ways more difficult than vehicles, as there should be no operator present.  the machine needs to tend and regulate itself.  even simple things like the mixture one does with a ball valve for years while proving the reactor, become untenable once you want the unit to run for hours on its own.  similar with grate shaking, ash take off, and internal reactor and filter conditions that need active monitoring.  or just how much junk in the filters you in actuality have to deal with once you've "solved" the tar problem with filtering.  we usually ignore these issues during early successful demos that the unit will make gas.  they bite nastily when you actually want real world ongoing operation.

a mess of money can be spent fixing these issues with exotic engineering and the most impressive materials.  but such can quickly make the solution irrelevant due to cost and completely.  what makes all this relevant in the end is value optimized engineering.  the challenge is to make the total cost and complexity input come out at a level tolerable for what one is going to get in retun.  

making one part good for 30,000 hours, when the rest of the unit is still a manually operated demo, isn't terribly helpful.  or delivering a 20,000 hour solution on all fronts to a user that really only wants a few hours a day is similarly imposing a price point not optimized for the actual user.

the current power pallet is a very specific value optimization directed at the use scenario i found most relevant for typical users. it is an attempted optimization for regular daily partial hour operation.  it is directed at the individual or business situation where one wants to run an 8 hour shift, or do a battery charge cycle, or provide temp power to a village, or similarly how we run typical mobile light industrial gensets.  these are usually considered 5,000 hour solutions.  we're trying for something in the same realm, and pushing upwards.  this is not a briggs and stratten rattler nor is it a continuous run utility type solution.  remember that 100,000 miles in a car is about equal timewise to about 2,000 hours, so 5k hours is not a small time.

when one moves into continuous run situations, you usually move out of the automotive based block industrial engines.  the ford power products or gm power train solutions are highly value optimized light  industrial solutions for this realm.  however, they are not a full industrial heavy block or with inframe rebuild capabilities.  a cat or cummins or deutz type genset is imagined to go for 15,000 hours before an inframe rebuild is needed.  then go for another 10k or so before a full teardown is needed.   they cost multiples above an automotive block based industrial engine.

you can also get more exotic and move into the oil field type engines, or exotic things like the marathon ecopower engine for domestic chp units, and have engines in the 30-40,000 hr realm.  the topic of much of the diy slow speed engine world is to figure out how to do this for something less than the $15,000 for 5kw that is what the ecopower unit costs.  this is where all the lister and china diesel solutions come in.

the problem is the price point of the off-the-shelf higher end solutions are often much more expensive than simply replacing the lower priced engine.  if you are only getting 2x the life, at 4x the cost, you didn't make much progress.

this is why one highly regarded chp provider in the us (tecogen) uses the cheaper automotive based engines, and changes them out for new ones on a regular schedule.  they found this a better total value proposition than using more exotic equipment with longer run time.

on the genhead side things are less sensitive.  you can do long hours with an ST head, but you'd likely rather go to a marathon, mecalte, stamford or leroy somer.  these are more typical heavy brushless genheads with more predictable longevity.  the marathon is generally considered to be cadillac of genheads (even though "cadillac" might now be the best metaphor here).  but any of them are good and adequate.


all of this is to say that once you have the thermal and chemical process architecture mature, and the automation to control it working reasonably, you can change out materials and engine/genhead modules quite easily.  

the hard part is doing the engineering to make the gasifier actually work without the typical costly crutches, and refine its integration with an engine.  switching engines or genheads out is mostly just ordering a different one and installing it.  the power pallet is designed to allow for easy change of engine/genhead as use requires.

similarly, the gasifier and filters can be made in all stainless simply by sourcing different sheetmetal parts.  we are now transitioning to an out of house cnc laser cutting service, which can much better control the health issues around cutting large amounts of stainless, so we'll soon be offering the gek in all stainless too.  you wouldn't need this for your continuous run situation, but it is available.

the most important change for your continuous run situation would be a different engine and genhead optimization.  the air cooled kohler and ST solution is not optimized for this.  the automotive block based solutions would be adequate, though you would have to change the engine every year or two.  a year is 8700 hours.  

there is also a spark kubota engine i'm looking at seriously.  it might be a reasonable solution for higher longevity on the small end.  it is only 860cc.  you can't get the automotive block based engines under 1600cc.  thus we are using the v-twin implement engines.  these are the only reasonable spark engines regularly available in the under 1600cc market.  even the nissan 1.1L and ford 1.3L are now gone.

if you want the full 10 - 12kw, this requires the 1000cc engine, which is only available from kohler in air cooled.  if you can tolerate less power, you can get the water cooled up to 750cc.  the water cooled engine will have more longevity and quieter operation than the air cooled one.  the kohler implement engines seem in about the same value engineering realm as the automotive engine solutions.  the main issue is whether or not you are using the air or water cooled versions.  a kubota will be above the kohler solution, as will the price.

yes, all this gets confusing.  there is no one correct answer.  there is a balance of factors and value engineering decisions to be made.  hopefully the above helps a bit to illuminate why we've made the ones we have to date, and other ones possible in the future.


jim

[Vinnie J]

Wow. That was one heck of a reply! thanks for all that info. I need to come up with better questions.

If the PP is upgraded to 15 or 20 kw, it runs of a ford engine, how many hours of life can be expected from it?
Just doing a little quick math, i may have this wrong, but with the kohler we are talking about 36 cents per kwh by the time it dies. That is kind of a buzz kill.
I would really like to get a full PP but i dont think i can afford 36 cents pkwh. of course the price comes down with the number of engines you buy but still... i dont want to be replacing engines every year and a half.

[Vinnie J]

by the way, did you guys ever hit 200 hundred sold? if not are you extending the sale until the end of june?

[David MacIsaac]

Thank you for the detailed reply I will be looking forward to getting a GEK operational and contributing to the development effort.  I must say that I am impressed with the common since approach to your development effort is taking with the high accessibility to this technology for a layperson.  Thankfully I have basic welding / fabrication skills with a hobbyist’s skill set in computer programming and hardware engineering so I believe the technological and manufacturing requirements for the GEK are well within my abilities. I have this year moved out of the urban setting to a 25 acre treed lot with all of the standing dead fall I need to begin chipping.  Currently due to limited funds and time I can’t get involved at this time but I am committed to contributing where I can.  I am weather proofing a workshop on my property now and will be ready to begin fabricating in the fall.  Do to resent changes in the method of procurement of power in the province of Ontario ( http://fit.powerauthority.on.ca/ )we are able to get 20 year fixed price contracts for the generation of green power and this include biogas and biomass in the category.  A GEK generating a base 10 kw/h 24 /7 would net $1250 a month under the Micro Feed in Tariff system (less than 10 kw/h).  One of the most advantageous aspects of this program is only one meter would need to be installed in an existing power distribution system on my property to begin selling power and only a inspection by the local electrical safety authority is needed to secure a standard offering contract no approval process for installations less than 10 kw/h.  I will be modifying the basic GEK set-up with a more elaborated heat exchange system for CHP and drying feed stock. Some points of interest for me are using Geopolymers for a reactor and using an investment casting process to include all of the air preheating, tar recirculation, combustion chamber shaping for better gas mixing performance, etc. The use of Mazda RX7 rotary motors for longer run times between service intervals and the better combustion performance for fuels with a slow flame front.  The inclusion of ICE exhaust catalysts inside of the exterior heat shield of the reactor to ensure complete combustion of gasses and heating of thermally challenged processes. Final exhaust stage carbon fixation in a photo bio-reactor generating algae for soil augmentation and livestock feed supplementation. Developing a carbon credit brokerage and receiving feedstock for free where available and reciprocating with carbon credits for business who supply feed stock.  I will be trying to post an article a month summarizing some of my ideas and technical resources I have found.  Ultimately I would like to make a personal gasification system that has the capacity to reduce all materials that come onto my property, that don’t have a recycling value high enough to warrant collection.  

Thanks for the effort,

David

[rutman]

If the goal here is production of electric power, doesn't it make more sense to purpose-build a heat engine such as a Stirling or what have you, and attach this to a generator (not genset, an electrical generator), instead of purpose-building a gasifier to partially combust to syngas and then using a genset for final combustion?   I would think the single step process would be more efficient.

[JohnnyPayphone]

I would be very interested to see a side-by-side comparison of efficiencies of a gasifier/generator versus a Stirling engine on the same fuel.

It's worth remembering that the GEK started out as a kit for the user to experiment with gasification, not necessarily for electrical production.  It would be "mission drift" for us to get into other methods of electrical generation (although, outside of work we're all big power hackers and were running All Power Labs off the grid on solar and biodiesel).  Oftentimes our customers have mitigating factors that make this solution the most desirable.  For example, if a local utility is paying $0.09/kW for electricity, you'll save more money supplanting your existing electrical use at a higher rate than you will selling to the grid... but if you're somewhere with no electricity, the Power Pallet's value skyrockets!  Similar situations arise when you have a customer who is paying to dispose of biomass.  Suddenly the ROI becomes exceedingly desirable.  For this reason, we are committed to offering gasification products and will continue to specialize in them as the world leader & industry innovator below 20kW.

[rutman]

i haven't found many stirling engines off the shelf at tens of kw so thats one strike against.  But any external combustion  heat engine, e.g. a steam turbine w. boiler or even an old fashioned locomotive-style steam engine, would do - India and China are cranking them out for factories that have waste heat sources to produce onsite electicity.
I didn't catch how the factors you mentioned weigh against heat engine alone vs. two step gasification->heat engine (assuming the  lone heat engine can accept the same fuel).  One advantage I have heard is the gasification products are much cleaner than straight up combustion would be.  And I understand the perils of mission creep - but if someone's just looking for electricity production off biomass maybe external combustion is the way.

[JDRay]

There's a company, Cyclone Power Systems, that's continuing development of an external combustion engine for a variety of uses.  They have a business partner that is developing something akin to the Power Pallet, but based on the Cyclone engine.  The Phoenix-10is a 10 kW power plant that runs on waste oil.  They have a similar system that they say puts out 40 kW.

Cyclone power has a nice diagram of waste heat recovery for energy production with a grid interconnection.  According to the information on their site, the engine is designed to run on waste heat (flue temperature) in the 500-700 degrees F range, with a capacity to run at lower temps with less efficiency of operation.  What I've seen around the GEK site looks like the temp of the flue, even post recovery of energy with the integration, is in that range.  Maybe a Cyclone engine is a way to capture more energy, or a better alternative than a standard I.C. engine.  Based on the video of their WHE, it sure runs quiet.

By the way, just to be clear, beyond reading a bunch of their material and exchanging a few e-mails with them, I have no relationship with Cyclone Power Systems or Phoenix Power Group.  I'm just interested in what they do.

Cheers.

JD

[rafit]

Hi JohnnyPayPhone,
you said "... industry innovator below 20kW...". What are the critical issues that will constrain me in scaling the GEK beyond 20KW to say 150KW? Are there any known red lines and pitfalls that make simply scaling up the dimensions a non-starter?

Thanks.

[bear@apl]

Scaling of dimensions won't be linear. Common wisdom is downdraft systems don't work well above the low 100 kWs.

Cheers,
Bear