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This solar fire+steam stuff is going ahead as is then?
  • I know I know, I'm just some amateur talking instead of doing.  But seriously - the math just does not add up here.
    The solar fire collector, according to is 400 bucks per peak kW sold.  I searched the wiki and couldn't find anything on the actual materials cost - even assuming the best case scenario of that being the power actually transferred to the steam, it's not enough to get anywhere near $1 per peak watt as hoped.  The whitecliffs engine alone got about 20% efficiency.  That would be almost $2 per  peak W of electrical output for the collector alone, right there - and that ignores, well, everything.

    Either the solar fire people are charging a very large profit margin, or there is no way this could work out cheaper than photovoltaics, which are about $2 per watt.  Where is the cost estimate that was used to come up with this $0.5 -$1 per watt figure?

    Because I'm more than a little concerned it is going to be a train wreck - all this work is being planned around something when the math just doesn't work.  If the homework has been done, why is it not on the wiki?

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  • what about something more like this:

    but a bit bigger?
  • @ Gregor - It seems that OSE is ready to become independent of "corporate control" at all cost.  Not something I necessarily disagree with.  But unfortunately, OSE is not yet a collective.  The word collaboration is being thrown around a plenty, but in reality, very few are making the big decisions at the moment.  They can only do so much by themselves.

    The infrastructure needed to create a proper collaborative effort is simply not there.  So we are stuck with a few at the top, probably Marcin by himself, doing what he thinks is best.  I have to admire him.  But at the same time, I share your frustrations when I see mistakes being done and no clear way to help.

    So one might ask, what is to be done about this?  The first step, is "they" need to be willing and able to accept the help they surely need.  Then, this word collaboration has to be taken to heart and any sense of ownership to any of this, removed from their minds.  These are difficult things for the ego to accept.

    I agree with you that more research needs to be done, but more importantly, core ideologies need to be polished up and ratified BY THE COLLECTIVE before any meaningful progress will happen.  As a group, we have skipped over these things and moved on to "more pressing" matters.

    I encourage you to be patient.  I think we can pull this off eventually.

    Much like yourself, I will certainly do my best to ask the hard questions.

    The Dawg

  • @Dawg

    Reading Marcin's 'manifesto' here, he's made clear that he isn't planning on doing extensive organizational or coordination work. He's sticking with his core competency of designing and building stuff. He is expecting others to "step up to the plate" and handle the finances, website, systems engineering, and probably even high-level goals. If you're willing to devote full time to this without pay, that person could be you. Or maybe aneiren can fill one of those roles, if he has the time. This is why it seems so unclear whats going on to the rest of us, because Marcin isn't putting any effort into explaining it. He's expecting someone else to.

    We do need leaders...making decisions by committee isn't usually the best thing. We need people who are spending 100% of their time on this to be the best informed, synchronize everyone, etc.
  • @ Jason - As a matter of fact, I have offered to perform in this basic way.  Marcin and I are wrestling with ideological differences at the moment.  We are in the process of finding common ground.

    Since you mentioned this "manifesto" I will quote from it.

    "I’m inviting everybody who is capable of
    contributing to the project to positions of leadership. But not as a
    subordinate – but as a co-creator. That means a lot of responsibility
    falls on you."

    What has happened here is I stepped up to the plate to take on a certain authoritative role and instead of being treated like a "co-creator", I was given a set of rather strict rules and requirements to follow.  This to me is contrary to being treated like a peer or equal.

    Because this position does not exist yet, a discussion needs to take place as to how it will run.  First responders to the call should be left to formulate how they will interact with the project as a whole not micro managed and dictated to like payed subordinates.

    So the discussions are on going.

    The Dawg
  • @Dawg - While I can understand your frustrations, I think some understanding and further patience is call for with respect to OSE as an organization.  Since Marcin's TED talk, visibility and participation in OSE has grown enormously.  Surely you can see that it's difficult to grow from a group of a few dozen people to several hundreds of people -especially when that happens in a matter of months.

    From what I can see, Marcin and OSE are taking steps to improve things.  There has been a lot of work done lately on how to setup, join, and manage OSE projects.  There have been discussions around documentation standards that should simplify and clarify things.  There have also been a number of discussions with people who want to take on leadership roles within OSE - you know this because you state so above.  While solutions to technical problems can often be implemented immediately, solutions to people problems usually take a lot longer.  We are trying to build teams at different levels of the organization and assembling good teams take time.  Team composition is critical since they need to be able to work together.  A team that can't work together does more harm than good.

    You take some exception to the term "collaboration" above.  While I'm sure that there are many interpretations of the word, I view it as "working together towards a common goal".  The existing OSE leadership team is actively working on trying to figure out what it means to work together in an organization that largely consists of volunteers.  They are also trying to figure out what the short term goals are and how to prioritize the high level goals.  Some of those efforts are bearing fruit.  Solar power generation has been identified as a high priority goal, which I note was the original topic of this post. @gregor raises some concerns about Solar Fire that should be addressed, but the conversation has been side-tracked into a discussion of leadership and organization.  May I suggest that such topics might better be discussed as threads in the Organizational Development forum category?

    On the topic of ideology, you mention that you are having some differences of opinion with Marcin.  He has stated most of his views on the long term vision for OSE, I'm interested in hearing your views as well.  How do they differ?  Why do that differ?  Are they substantively different, or just different on how to get there?  Why not post them over in Organizational Development?

    Criticism is a useful tool, Dawg, but we should recognize that it's a tool that needs to be used carefully.  Ideally, it is a tool that is used for positive change.  Used bluntly it hurts people.  Suggestions are better than blunt statements -as if they were fact.  Questions are even better because they promote discussion, rather than shutting it down.  I believe that you are really trying to figure out where the problems are and trying to make suggestions on how to improve things.  Hopefully we can all work together to achieve the vision that Marcin has shared with us.

    - Mark
  • @Dawg I also offered to assist and I was told to wait for some to give me orders. Marcin wants to maintain control but doesn't have the time to spare on leading.
  • @mjn - Perhaps you're right Mark.  We've veered a bit off course, topic wise.  But what I am talking about is the root cause of gregor's concerns, so in a round about way, it is on topic. 

    As far as being hurtful, keep in mind that much has gone on in the background regarding this.  Marcin and Co knew this was coming.  No one has been blind sided.  I hope no one is feeling hurt in any way.

    I appreciate your thoughtful input.

    The Dawg
  • It just seems apparent - from the documentation in evidence at least - that no preliminary feasibility study or reasonable due consideration of other options has been done here.  I have a hard time believing this is true, but that's sure what it looks like.  I occurs to me that maybe people are trying to port the method that led to success with e.g. the CEB press to this problem, but the internet and history is littered with people who were a lot more careful and better with the planning that came up with solar power systems that never worked out.  The back-of-the-envelope approach might work for farm equipment but it isn't going to work here.

     MJN, from your wiki activity you seem to be part of this team:  Is it the case that the homework has been done but not posted to the wiki or has it just not been done (which would seem quite a hole in the planning)?

    If the former it should be posted, as it would help give prospective developers the confidence that they are not just wasting their time I think, thereby encouraging contribution.  Although I acknowledge again that I'm one of the ones here with more enthusiasm than expertise, I haven't bothered to even look to see if there is anything I can help with because it appears that the project is doomed.

    Similarly, I cannot find any evidence on the solar fire page that there has been much investigation of, say, that parabolic bending is so bad.  I would think that they considered these options to some degree of diligence, but they didn't post it or say so, so we can't know. 

      All this seems to make it clear that documentation is indeed important, not just of the finished product but of the design process - what was considered and rejected and why, too.  Otherwise we cannot know if they considered and rejected using, say flat sheets of aluminum instead of glass mirrors for example, or just jumped in without considering it.

    To put forth completed designs without this sort of background of where they come from is contrary to the whole open source thing;  it seems like someone is assuming that the design is finished and there is no more room for improvement.

  • While there may be pitfalls and missteps along the way, the good thing about the whole process we have here is that we'll figure them out and fix them. When it is duplicated at FeF, and equipment is running from it, its going to quickly be evident whether it is the right approach. The most important thing imo is that any mistakes are documented in addition to the successes, so that it can be a learning experience. Covering up failures is the opposite of what we want to do.
  • i only briefly looked at the solar fire stuff but from what i can tell it was chosen mostly for its ability to be fabricated.

    it would be nice to crunch the numbers on this better. if it turns out to be much cheaper to simply buy a solar panel maybe this project could be put on the back burner and just have recreational input and improvements.

    32 square meters of mirrors.
    12-15 peak kilowatts of output (depending on location).
    Focal point temperature over 700 C.
    Price: 5000 - 7500 USD (depending on quantity)
    Roughly 400 USD per peak kilowatt.

    do these costs include the generator?

    "Criticism is a useful tool, but we should recognize that it's a tool that needs to be used carefully.  Ideally, it is a tool that is used for positive change.  Used bluntly it hurts people.  Suggestions are better than blunt statements -as if they were fact.  Questions are even better because they promote discussion, rather than shutting it down.  I believe that you are really trying to figure out where the problems are and trying to make suggestions on how to improve things." 
    i think we should post this at the bottom of the forum.  maybe we could refine it a little for length
  • Buying PV panels is not an option. We cant make panels (for now) and it doesn't teach us anything.
    Even if the solar fire system does not output as much energy as hoped, it keeps outputting what it can for life.
    Thats a lot better then nothing.

    Ive researched this type of system a lot and 1 big improvement would be to use an evacuated boiling chamber instead of a metal one.
    This can be made from a metal box with a sealed pane of glass on the bottom. With an inner boiling chamber. This can improve heat capture by %35 and even more in cold air tempature regions.

  • @AzMaker - Keep in mind, the Farm is primarily running on gas powered generators now.  Yes I know there are a few solar cells also.  We can't make generators either but they work for now.  It's really early in the process, so lets get up and running with tech that is as green as possible then transition into the next stage.  We are a very long ways away from building our own steam engine in house, yet this is what is proposed in this case.

    So lets try and tally this up.  We can't make the mirrors, we can't make the steel, we can't make the steam engine, we can't make the generator, we can't make the copper wires.......get my point?

    Solar cells start to look pretty darn good quickly.

    I'm just playing devil's advocate here because I like the project from several perspectives.  But not enough discussion has occurred to really know where we're going with this.  I think the timing is off.

    Lastly, take my word on this, that solar fire system will NEVER just run.  It's way too complicated to just happily run and run.  It will need constant maintenance throughout it's working life.  Combine that with the possibility that it is very inefficient and you start to see why some are wondering what we're doing here.  On the other hand, solar cells do just run and run.

    The Dawg
  • When I say that PV cell are something we cant make I mean, we may never be able to make them well. The refining and doping process is very difficult.

    We can melt steel to make stock. We can melt copper to make wire. We can make mirrors with pane glass and a simple silver or aluminum chemical layer deposit process. The steam engine and generator are 100 year old tech.

    Even if the solar fire system is only used to preheat before it goes in the bio-pellet furnace its worth a try.
  • To clarify, I never argued that we should stick with photovoltaic as the sort of designated power source, not at all.

    To the contrary, what I am saying is that this *particular* solar thermal-electric system is clearly not workable (unless details which have not been made public exist which change the story which is highly unlikely at this point, and should not be the case if this is to be open).

    That doesn't mean we can't beat photovoltaics on price , both capital cost and running cost.  At all.  It does mean we will have to be a bit more clever about it.

    The only small scale solar thermal technologies that have been  employed successfully commercially that I know of (the white cliffs project was not a commercial project) are:

    1. Dish Stirling.  Not that these use *free piston stirling engines* I think some people don't know what this is, although I tried to explain.  See the wikipedia article on these engines before you dismiss this one.

    2.  Organic Rankine engines, I think probably only turbines (in some cases a car turbocharger was used).  An ORC turbine turns much more slowly than a steam turbine, making it more practical for electrical generation.

    Now further investigation is needed, but I have posted a couple times on this forum (click my name to see a list of my previous posts), with some significant if small degree of investigation as to the best heat engines and the issues around this type of steam engine chosen.  All things considered I like the free piston stirling engine the best, and it has been proven commercially already by several companies which are competing successfully with photovoltaics on price and running cost.

    Also, I suspect the people working on the steam engine will be loath to give it up, but the good news is they don't have to: steam makes a ton of sense for the biomass powered powercube (and therefore lifetrac).  That would be a productive place to put the expertise and work on steam engines to use.  There is still time to change course. Why give up the chance? 

    It can accept a much shorter run time between maintenance tasks, and the high power density of steam is useful in the powercube.  In this application piston steam engines have already been proven to work.

    Lastly I noticed looking on the recent changes page a while ago that Marcin mentioned that he thought there was a good reason that the whitecliffs team chose not to use stirling engines.  There was.  I OCRed the document and searched "stirling".  Here is one of the hits:

    Heat-to-Mechanical Work Conversion

    We would have preferred to use latest heat engine technology which promises higher

    heat-to-mechanical work conversion efficiencies. For example a suitable Stirling Cy-

    cle engine might be expected to have more than twice the conversion efficiency

    of a high performance Rankine engine of the kind eventually developed for White

    Cliffs, But in 1979 reliable cost-effective Stirling engines suitable for solar appli-

    cation seemed removed from near term availability; in 1987/88 this still seems fair


    That was 23 years ago.

    These engines have now been developed and deployed.  Also, did they have fluid dynamics packages of reasonable power back then?  Not readily available anyway.  Now we do, a desktop PC can be used to design an excellent engine.

  • Here is a video of silver nitrate mirror.

    As far as ORC goes this is the way I would go. But the turbine needs a lot of milling/machining, Everything else is off the self.
    You can substitute r143 coolant for pure ammonia.
  • *facepalm*
    I think my point is that we need to be a little more serious about this, rather than choosing a method based on how cool it looks in a youtube video.
  • Also, if we use a stirling engine that is, as the whitecliffs people mention, twice as efficient as the steam, the collector is half the size - boom, that makes it a whole heck of a lot easier to meet the price goals even without improving on the solar fire collector, unless the engine cost went  way up, which it won't.

  • I only posted youtube videos because its a lot more efficient then trying to write up an explanation of the general idea.

    I have been working out all of the energy output numbers for years and the most efficient system is a parabolic mirror concentrating on an evacuated collector going to a closed loop ORC turbine.

    I don't like Stirling engines because they have low torque.

    The key though is that we do something physical and call that v1 and move forward from there. :)
  • But it would definitely be a good idea to have a decent design, correct?  Prototyping is expensive and time consuming compared with being a little more thoughtful at the design stage.

    There is no point in rushing into something that we already know has no chance of working.  I think some people tend to be very tempted to simply go build, and when I had a basement to tinker in, in retrospect I think I did that far too much.  It is more efficient, and in fact faster overall, by far to get a reasonable design down first.  Do some computer simulations and some cost estimates.  That has not yet been done.

  • I think the solar fire design is okay and it is a fine 1st attempt that showes some solidarity to other diy groups.
    One finished project is worth 10 on paper. I say go for it and see what we get? 
  • i think the solar fire could be a good test bed for different types of generators/turbines and stuff.

    it seems like it could be pretty simple to switch out the solar fire design for a evacuated collector. or change the plumbing from a basic steam engine to orc or a sterling.

    i know mark is working hard on the steam engine design build so i definately think that will be a good foundation to build from.

    how do you guys feel about planning on having parts we can switch out for more advanced designs? would it work?
  • Yeah a quick change plate like the one on the lifetrack?
  • @gregor  wrote "MJN, from your wiki activity you seem to be part of this team:  Is it
    the case that the homework has been done but not posted to the wiki or
    has it just not been done (which would seem quite a hole in the

    While I am not directly a part of the Solar Fire team, I have been following it's development.  Thought it may not be obvious from the wiki (yet), Solar Fire was developed by Eerik Wissenz (of Finland).  Earlier versions of Solar Fire have been built and are in use in India.  When Eerik became aware of OSE, it made a great deal of sense to merge development efforts.  That merger is largely complete in concept, but there are a large number of details that remain to be worked out.  In particular, there is a body of documentation and information that needs to be transferred to the wiki - this has not been done yet.

    As often happens, there is a conflict between doing and documenting the doing.  There is a large push on to install a prototype Solar Fire installation at Factor e Farm this summer and use it to drive a steam engine for power generation (which explains my involvement).  Focus of effort is on getting ready to build another installation, rather than justifying it's efficiency.

  • It seems like 2 problems have crystallized out here:

    One, a lack of documentation.  I would argue this is sort of like putting a bunch of undocumented spagetti logic code up on an open source web site and calling it open.  Except that it's not quite like that; the main problem is that it is so expensive and time consuming to try something new in hardware, whereas it is trivial in software.

    At least nowadays, I guess maybe we should look back at the days and certain projects when it *did* take months and many thousands of dollars to compile a program (obviously that was never the case for most projects, there must have been a few examples of projects of such size).  Presumably they documented and shared results and the design process behind their programs much than they do today because re-trying those things was so expensive.  Open source hardware needs to do the same.  This problem is apparent in both the OSE and to a lesser degree the Solar Fire project.

    Secondly, and I think this only probably applies to OSE and mostly (hopefully) this particular project, is that there is nothing to document where there should be.  There no real design process at the beginning, although there is at least a bit for the steam engine itself now.  The house is being built with no foundation at all though.

    And I am not criticizing the solar fire project directly WRT
    performance or cost (just documentation a bit), they clearly spend a lot of
    time and effort on the project and it's a bird in the hand.  But
    combining it with a steam engine like the one proposed to produce lower
    cost electricity is an idea that is dead in the water.

    I and others have pointed out plenty enough that clearly shows a mistake has been made here.  We could look into it deeper, but there's no point when we are hearing that people won't change their opinions no matter what anyone says anyway.

      The stated goal of the project is not to make a test bed, or to be a opportunity to futz about with steam engines for fun.  It's to do something significant; produce a prototype which works *effectively* towards a localizeable low cost solar electric system.  In answer to the criticism people just ignore it or grasp at straws.

      To paraphrase Martin Reese: When my opinions are shown to be in error, I change them.  What do you do?

    A lot of people here are not even willing to talk about them and re-examine them.  Maybe it's the sunken costs fallacy kicking in.  But as I said the effort on the steam engine is not wasted, it can be applied to the powercube.

      There are a million little projects on the internet and videos on you tube with people "changing the world" by futzing about with reflectors and little engines and so forth.  Most of these people are just sadly deluded as they try to dodge and hide from complexity and reality rather than embracing and understanding it, and are therefore unable to interface to it and actually do anything significant.

    Crappy systems like the one proposed have already been done a million times. There is no need for another one.  This is an engineering project.  Building an engine that is already known to be non-workable for anything in this case accomplishes next to nothing.  It is not the case that you learn much compared with actually working towards the actual goal in an intelligent way.  It's a very inefficient use of time and money.  Kind of like expecting to develop a way to make ball bearings by growing tulips.  Interesting, fun, but doesn't help to achieve the stated goal.

  • what do you think or next course of action should be?

    we have maybe 10 people on the forum willing to help.

    i dont know if any of us have much understanding of the efficiency of these systems.

    i'd be glad to read up on some stuff. i just dont know where to start. or if it would help.

    should we try to contact someone at a university to help us pick a good foundation to build from?
  • @gregor

    >  One, a lack of documentation.

    Have a look at  This will give you some idea of the project milestones, including documentation.

    >  There no real design process at the beginning, although there is at
    least a bit for the steam engine itself now.

    Well, as you can see, I'm trying to inject some project methodology into the process.  I am a big believer in the design process, which is why I put the effort into the Steam Engine design.  As you might expect, that process has revealed some weaknesses and some ways to improve the product.

    >  combining it [Solar Fire] with a steam engine like the one proposed to produce lower 
    cost electricity is an idea that is dead in the water ...  Building an engine that is already known to be non-workable for anything
    in this case accomplishes next to nothing. 

    Well, that is your opinion, which you have stated on several occasions now.  Personally, I don't think it is DOA, else I wouldn't be putting my time into the effort. Rather, we have learned quite a bit in the design process, some of which will go towards improving the design.  The steam engine, in its current incarnation doesn't produce much power - about 3-4 HP.  As part of the design process, one of my team members (Andrew Buck) created a software simulation of the engine using it's current specifications that has led to several possible ways to improve the power output. We are exploring those now.

    Your statements that this is a waste of time really don't help.  It is an emotional attempt to get people to abandon the work they have been doing.  Instead, you could be figuring out what is wrong with the engine and helping us improve the design.  Merely complaining doesn't help us at all.  It's a process, Conor.  One that leverages the positive inputs from other people, maybe even you.  Help me out or be ignored.

    - Mark

  • @mjn - As usual Mark, some great points.  I think the root cause of the concerns is lack of communication.  Your efforts are aiming to correct this.  Thank you.

    Any chance that someone more familiar with Physics could look into the limits of efficiency for this process?  Lets say the theoretical thermodynamic limit is 45%.  Then an efficiency of lets say 30% doesn't look quite so bad in a way.

    One could also argue that because the energy being captured is "free" that efficiency is less of a factor.  Not sure I would agree but it's something to think about.  Either way, if there is some solid data to chew on, people are then in a position to decide for themselves if it makes sense for them to get involved in this particular project or not.

    The Dawg
  • @Dawg

    >  Any chance that someone more familiar with Physics could look into the
    limits of efficiency for this process?

    That would be a useful thing to do, I think.  As I mentioned previously, we did this for the steam engine and it was quite enlightening.

    Here's the main problem.  Solar Fire has already proven itself.  There is an installation that works, as best I understand it.  Perhaps it's not as efficient as we'd like it to be, but working results trump all theory.  Many are upset that the documentation isn't there.  Unfortunate, but that's the reality.  Given work done to date (outside of OSE, I might add), the emphasis is to create a second working installation at FeF.  Speaking from long, long experience, documenting things after the fact is a reality.  The documentation is important, of course, or else it really isn't open source, but many of the people actively involved in OSE are DOERs.  If they think they have enough information to make something and get it to work, they'd much rather do that than fool around with theory and design.  It is neither right nor wrong.  It is a style of action.  As OSE gets more organized, I think that we will see small teams forming around the doers documenting what they do so that others may follow.

  • @mjn - Mark said: "The documentation is important, of course, or else it really isn't open

    To be honest, I think it is doubly important to document in Crowd Funded Open Source projects.  People are sending Marcin money to complete "the dream", not build himself a nice facility for free.  Keep in mind, this is not a brand newly created project.  OSE has been around as an entity since at least 2008, maybe earlier.  How long does it take?

    Now, before calling me just plain negative....:) allow me to be Devil's advocate for another moment and say "explain to me how we tell the difference between an up front organization and a freeloading one".  One way might be to gauge the level of documentation and open sharing that is going on.  This would include the sharing of crowd funds also.  I might add a few other things like accountability and cooperation/collaboration on important decisions.

    To my knowledge, non of this is being done.  Knowing this, when do I start asking hard questions?  At what point do I start sounding like a bitter contributor?  You get the idea.

    Ok, this dead horse is now dust....:)  If anyone would like me to share more on this, just send me a private message.

    The Dawg
  • Summary: I think one misunderstanding we might be having is that we're judging the technology based on competing directly with the current market stuff, like being cheaper than solar panels, etc, when the tech was actually chosen based on the OSE Specifications.

    If you look at the solar fire + steam engine from the perspective of the OSE Specs then they seem to make some sense. What does everyone else think? We should also have design rationale pages for the solar fire + steam (and all tech) that explain how they meet the OSE Specifications, and rate other systems based on the OSE Specs. Most of these questions have probably already been addressed, it's just hard to find where the information is right now.

    The steam engine scoring system metric used seems geared more towards finished products and not about whether or not to choose a particular technology, but the theory part of the OSE Specifications page seems to be useful intuitively if not metrically. There are some justifications for the selection of the steam engine in several places, it would be good to have centralized places to read all of the justifications so they can be fully judged. Here are some pages with some more info:

    More info on other technologies can be gathered and then they can be judged based on OSE specs. An open source stirling + some other solar concentrator system would be great as well, especially if it can compete with the commercial systems! It's true that one of the OSE specs is to meet or exceed the performance of industrial counterparts, but that is also only one of the specifications. Energy is very important so it's less important that the technology can compete directly with it's industrial counterparts compared to having the means of producing the technology.


  • I have an idea that might help to solve both these problems at once:

    An adversary system.

    1. On the solar concentrator page, there would be a section "Potential designs for prototype II"
    in that there would be several subsections such as:
    ===Organic rankine based===
    ===Steam based===
    ===Stirling based==
    ==Collector-focussed design==
    ===Trough collector===
    ===Array of flat heliostatic mirrors===

    (of course they cannot be designed in complete isolation, but people working on the steam can look at what is happening on the collectors and say "well the cost estimate is in for the extruded trough collector one and the tables on the page show that the 100x conc ratio one with half insulated absorber tube, for which the efficiency vs. temp table shows that when combined with the linear steam engine, when combining the cost estimates we did last week, looks like it should produce electricity at (shows estimating method) maybe $X per watt materials cost and Z person-hours of assembly time with tool capital cost of W - not bad!")

    ( I wouldn't add all the ones you can think of all at once, let people add them as they spin out of the rest of the design processes as interesting options)

    We have to divide the design approaches into groups somehow, and engines and collectors is reasonably natural.

    2. The community votes on which they think should be chosen. This is only an information gathering tool which is used by the leadership and the community, there is no risk of poor decisions due to bias by a mob of redditors that shows up or something because the leadership would notice and prevent such issues from affecting their judgement.

     It could be done through the wiki too, with the vote of each contributor correlated with their activity on the wiki and maybe team culturing info, then different statistics could be produced: results of the voting within only the people that added to the pages at some point (and therefore are more likely to know the issues), are engineers (from team culturing info), the population size-corrected opinions of  different groups (to compensate for biassing of the results due to an influx of certain enthusiasts who might not have really read the pages carefully) etc.  I think the wiki supports polling.  The voter correllation data could be scraped with a perl script then dumped into a database from which stats can be extracted if no existing solution is available.

    The community can explore the design-space, and in detail.  By design space I mean the problem space that includes all possible designs.   

    There are some rules that must be followed for this to work:
    1. Design criteria and guidelines specific to this particular tool should be available at the top of the page, and in reasonably compact form.  These are the all and the ONLY criteria that decisionmakers will care about in their decision making, and they should not change much after the word go, if possible.  The compactness need conflicts with the latter to some degree of course, but the best compromise that can be found.  

    2. At the time the design is chosen by the dictator, all and  ONLY the information on the page and maybe 2 links deep or something (so references can be verified) may be considered, except in the cases where information cannot be shared in it's entirety publicly due to copyright (in which case the argument such documents contribute needs to be made as available as possible to the other contributors by quoting sections etc. and the docs should be available to the maximum legal extent to those who ask for them).

    This makes sure contributors can have confidence that their time spent contributing accomplishes something, which will encourage contributions.   They know they see the entire body of existing work so they know what does and does not need still to be done, etc.

    There are at least 2 things that need to be done for this approach or some variant of it to be implemented:
     1. Get the existing design documents up so that we can pick up where the design was left off.
    2. Leadership needs to send the right signal that the decision to use the approach has been ratified, if it is.

    This could accomplish many things in one go:
    1.  It integrates documentation directly into the design process.
    2. It allows ready collaboration within the entire community.
    3.  It gives contributors confidence their time spent contributing is well spent.  In the hardware design communities there is not currently the same culture that exists as there is in the software community.  We need all the help we can get bringing in contributors.
    4.  It gets the critics off the backs of the people in the building and on the project post-design.  The most ardent and useful critics are the ones that are critisizing because they want to see the project be done well.   If someone says you are doing it wrong, tell them how the design process goes, and when they see that they have in fact an effective route to correct the design deficiencies of the current prototype that they see, with such improvements being incorporated in to the next prototype if it does turn out to make sense to do so, hopefully they will go make their argument well, in detail and preferrably quantitatively, on the wiki.  Therefore being more useful and easily integrated into decisionmaking.  

    How it could fail:


  • 1. The page becomes to big to be reviewed, or the signal to noise ratio
    becomes too low, with good design gettign buried.  I don't think this
    will be a problem because the wiki page can be summarized as we go
    along:  Bob says he's concerned about the possibility of the mirrors in
    the current multiple-flat-moving-mirror collector design seizing in
    winter due to ice, say.  Mary gets back with some info about how ice
    accumulation is reckoned for in bridges and comes up with an estimate
    for how much ice could accumulate in one day or night (whichever is
    most relevant) in the worst night in 3 years typically in various
    weather zones, and an estimate of how this would effect operation.  
    Kerry gets back and improves the estimate and shows the force of the
    chosen actuator has to be at least this much for the solar fire
    design.  Someone else suggests applying grease to reduce that torque,
    someone else says maybe anti-ice paint would work and explains how anti
    ice paint works.  Yet another person points out that the actuators can
    be designed to have enough torque according to kerry's estimate but the
    cables would break or wear out fast, but that if the hinge mechanism is
    modified in this easy way, which is no harder to build, the problem can
    be obviated.

    Then Jim comes along and summarizes the whole exchange into "We would
    need actuators with probably about this much force (include estimate) 
    to deal with the estimate of the 3 year worst case for ice buildup in
    the current design, and this produces (this problem for this reason,
    show estimates) .  Designing the hinges in this way and the torque goes
    down to (show esitmate): (show solution) which is enough to solve the
    problems without complicating the design and without the maintenance
    that greaseing stuff needs."

    The change history is stored, so  when someone points out that grease
    actually lasta many years without reapplication and the process
    continues (hey you can't know everything and that's progress) and
    changes it again totally,  then someone else notices that estimate
    doesn't work in if there are conditions where the snow wipes the grease
    off (whatever this is just an example) they can go to the edit history
    and the work of mary bob an kerry is still there and can be used.

    2.  The design exploration is not advanced enough to make a good
    decision.  Well then there just isn't enough, or skilled or
    enthusiastic enough contributors, which is a problem no matter how you
    work it.   Or it is not harnessing enthusiasm well enough, but it's
    certainly much better than the current approach.

    Ideally, you could even actually produce a good finished design with
    this process, because there is hardly an argument better than a really
    good, known to be good (with all realistic cost estimates that look
    good, real world examples increasing confidence in practicality of the
    systems etc.), but at some point the adversary part may mean that if
    one design really gets ahead the competition will give up and the
    winners just call it a day and go, but some people may stick around and
    finish it, since we know that is the plan anyway, and we have
    confidence that the design, since it is superior, will be chosen and
    therefore the time to finish it is well spent.  

    Note that the Dictator, when it comes time to pick which design to
    finalize, does not do much design work.  They don't finalize the
    esitmates or whatever, they would have done that yesterday, instead, if
    the schedule is to be kept.  Well there might be some filling in of the
    blanks when they notice low hanging fruits here or there as they do the
    review process.

    I see no real problem with extending the schedule if it is really needed though.

    3.  Costant switching between design paradigms is a problem.  This
    won't happen because these are *arguments* which are on the page, not
    just design details, although having a design is a very good argument. 
    Therefore adding " but we already have this existing system to build
    on, and as a result if we go for this steam design in the next stage it
    will cost a total of $x and Y person-hours or so to reach prototype II,
    whereas if we choose approach B then it would take $Z and Q person
    hours, for what is really a small benefit, which we just clearly can't
    afford." will prevent unecessary switching if it is strong enough.  

    Hopefully, in the next several months, the design process will proceed,
    and the figures mentioned will improve to the point where there are
    design options on the table which are reasonable well worked out and
    which improve upon the existing design while being well worth it to
    prototype, and depending on funds etc. available, the best would be

    There are 6 months until construction on prototype II begins, and this could be a valuable experiment.

  • Just wanted to clarify that when I say dictator I am referring to the established benevolent-dictator-for life model that is proven in software, it is not a criticism at all, just the term used.
  • @gregor
    I made a wiki page for the design selection:

    I don't mean to be rude but please get on the wiki and start adding useful information to the
    categories and please don't spam the forum. Anyone with google and a brain can start collecting links
    and metrics for each design on the wiki.

    Thanks for your help!

  • @gregor
    While the organized collection of information is to be encouraged, one question I have is,"Why do we need to make a choice?"  The three engine designs mentioned (Rankine, Steam, and Sterling) each have their advantages and disadvantages.  As you pointed out above, the Steam Engine will be useful regardless of how it is specifically used.  I feel similarly about the Sterling Engine.  One of the powerful aspects of open source development is the parallel exploration of ideas.  Personally, I encourage the exploration of all of these approaches - all the way to prototyping.  Let's get real experience, real OS build plans, and compare them.  Let's learn what they might be best at - rather than guessing.

    While I picked on the engine designs, the same applies to solar concentrators, too.  Trough designs are likely to be substantially simpler to build than parabolic, but less efficient, too.

    About the only argument that might be presented against parallel development efforts is the lack of resources.  Tis a silly argument, IMO.  People will vote with their time, energy, and money.  Personally, I put my time into developing the steam engine.  I know of at least one person who is similarly passionate about the Sterling Engine.  No one has stepped up to push a Rankine engine - which doesn't mean that it lacks merit, it just lacks someone to pursue it.  There are already dozens if not hundreds of people involved in OSE right now.  Properly motivate, we can do anything.

    - Mark Norton

  • Since this forum has gone far off topic. I've posted my reponse in a new forum:

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