Wednesday, December 26, 2012

Quick re-frame on subsidies enjoyed by different energy platforms

Hello Reader!

Yes I use the singular becaue
1) The chances of a choral reading being don of this or any other post (or blog for that matter) is SLIM.
2) I think most of the hits are robots indexing the content... Sad little robots without so much as a gear or actuator to call its' own. Just some navigation algorithms and n appetite for new URLs...

OK in my inbox was a link comparing the outcomes of subsidies for different fuel types in term of how much the resulting energy costs. Sobering in a good way.

Check it out

I know Obama got teased for saying his energy plan was an "All of the Above." But it seems we are all acting that way already. If you have a grid connected home, even with solar panels you dip into the coal/gas/nuke/hydro grid sources and then drive a car or accept foods delivered closer to your home by trucks, cook it up with natural gas or electricity, keep it cool with electricity and then read over by the window for some direct solar but aim your chilly toes at the fireplace or tuck them under the dog. So the question becomes not if but to what extent we partake in these different sources and then what we get from each in return. No?

Wednesday, December 12, 2012

Market Research - A great way to procastinate

So the DOE turns out to have about half its money tied up in keeping our nukes going and safe(ish.) Yikes. They get raked over the coals (oh see what I did there? :^) ) about being green cheerleaders and a great deal of their freedom to move is hemmed in by all that incumbent energy. OK off the soap box.

And on to the thrilling subject of Soft Costs in PV installations. YAY market studies! YAY NREL!

From a very fresh  study of Soft Costs of PV installations carried out in 2010 by NREL:

Including assumed permitting fees, in 2010 the average soft costs benchmarked in this analysis total $1.50/W for residential systems (ranging from $0.66/W to $1.66/W between the 20th and 80th percentiles). For commercial systems, the median 2010 benchmarked soft costs (including assumed permitting fees) are $0.99/W for systems smaller than 250 kW (ranging from $0.51/W to $1.45/W between the 20th and 80th percentiles) and $0.25/W for systems larger than 250 kW (ranging from $0.17/W to $0.78/W between the 20th and 80th percentiles). Additional soft costs not benchmarked in the present analysis (e.g., installer profit, overhead, financing, and contracting) are significant and would add to these figures. The survey results provide a benchmark for measuring—and helping to accelerate—progress over the next decade toward achieving the DOE SunShot Initiative’s soft-cost-reduction targets.
We conclude that the selected non-hardware business processes add considerable cost to U.S. PV systems, constituting 23% of residential PV system price, 17% of small commercial system price, and 5% of large commercial system price (in 2010). These processes present significant opportunities for further cost reductions and labor-productivity gains.

Further on:

"Average installer expenditures on customer-acquisition activities totaled $0.67/W for a typical 5 kW residential PV installation: $0.11/W for system design, $0.33/W for marketing and advertising, and $0.23/W for all other customer-acquisition costs."

Our takeaway? Every one has got to think about ways to speed up the process. Permitting. Customer education. Finance prep. Project management. The whole thing.  Even negotiating the rebates and incentives imparts a cost. Lots of these are figured on a per kW basis (and segmented Residential/Commercial) but I'm still digging for which costs are better understood as a per project basis.

These numbers are a test of your glass half empty vs half full sense.  Seems like there are plenty of places for smart people. Take a look and see what you make of these two studies from NREL:

Photovoltaic (PV) Pricing Trends: Historical, Recent, and Near-Term Projections
Benchmarking Non-Hardware Balance of System (Soft) Costs for U.S. Photovoltaic Systems Using a Data-Driven Analysis from PV Installer Survey Results

Wednesday, November 28, 2012

Going into orbit?

You will want to pack these:

Entech's Stretched Lens!

Super clever deploying of just the bits that do work. Since there is no windloading and only micro gravity... the designers are challenged to rethink what is and is not needed. This seems to have slimmed things down to the barest of minimums.

take a look:

Smart, no?

Tuesday, November 27, 2012

What is wrong with this picture? CONTEST!

Seriously... check this out:

it is from the blog at solfocus...

I get that it is a big installation and every thing seems to be working... Maybe they are not actually tilting accurately at the time of the photo but I'm thinking of something WAY bigger.

First reader to 1) leave a comment below and 2) recap in an email, to me what is so wrong with this picture of a solar collector array... gets a prize. The prize? I mail you, express mail anywhere in the USofA a batch of chocolate chip cookies or gingerbread cookies if you are allergic to chocolate. Butter allergy folks get my condolences as a prize...

There are two answers IF you look at the map below and consider the campus more broadly... now that I look at it.... SO TWO PRIZES.

And yes, if you come up with a third smart concern... there will be more cookies.

Side note:

Funny thing... if you go to Google Maps (say for a different view) The pictures of that site were taken before and after the installation of the SolFocus gear. The near pictures are older and the far pictures are newer. So you can see the site prep for the array and then the array just by zooming back and forth! Confusing but neat.

Check it out while it lasts (the links that is, they keep updating the photos so this before and after trick is just for now but very worth a look.)

(you might need to scroll around a bit to see the silver rectangles even the pool comes and goes!)

View Larger Map

You might have to search for Crafton Hills College Campus Drive in Google Maps to see this...

I'm still working away... found a report again you'd like

This report (link is to a PDF) is a good look at the troubles that come with plain Fresnel Array concentrators. There might be some subtle differences for Cassegrain collectors... but all these high concentration operations have some serious consequences on the expense and complexity front....

For an example of a Casegrain array look at SolFocus

The concerning items include extreme aging of the cells (hard job) Risk at misfocus (although they had some good news there for the Fresnel, safety wise...) the demanding focus/tracking requirements.  A good read and a hint as to why I think we need a different approach.

Sunday, November 25, 2012

A look into the pyschology of ROI...

Here is a neat (OK somewhat disheartening) story in Joseph Romm's blog (I think it is a blog) over at

It is a long article so stick with it and get to the more thoughtful ROI (Return On Investment) aspects. Like this bit
Lots of equipment is changed at end of life, regardless of energy efficiency. What often happens is that an engineer will say: “Inefficient boiler X will pay for itself in 10 years in savings over the existing model. More efficient boiler Y will pay for itself in 15 years. We’ll take the less efficient cheaper model.” But ROI calculations on these projects should only consider the delta between the cost to replace equipment (which would be spent anyway) and cost to replace with more efficient equipment.
 Makes sense. This is how I justified my change in heating system from a replacement to a re-engineering. The base expense is just going to happen so that is the zero point. Every candidate gets credit for doing the job for that least price. The alternatives then have to have additional benefits that merit the premium over the base. ROI is nice but this is not an investment so much as a prepaid expense. This is expense I cannot easily avoid (my sweater and coffee/soup expenses could not fix the heating problem) so I should not use investment notions, exclusively, to evaluate it.

We had a similar issue with picking a car. (this one does not play out well, sorry to say.) We wanted a new car (to boost reliability as this was a high value for us right then) and sized up 3 year old cars of the base models and found the "roll off the lot penalty" seems to have vanished for base models of the low end Civic Corolla type car. Part of it is that the quality of cars has gone way way up. The rest must be some intersection of lower markups and a better sense among buyers of the value of hanging on to their car. Anyhow, for each car we took the base model expense, then around $15K and our relatively modest annual miles driving and three cost scenarios for gasoline 3,4 and 5 dollars per gallon. PLUS the "get a new battery" penalty on the hybrids at 5 years or whatever it was. That was the killer. The mileage improvement was real but the cost of getting it was also real and we thought that the best comparison was the delta. If we doubled our miles driven in a year then we had an argument for a Hybrid. Instead we figured we could go with the still efficient (in this case Civic) and just try to clip off a day a week with telecommuting and or carpooling. About the same carbon footprint. For far less.

Super read I thought.

Monday, October 22, 2012

Prototyping is a picky little devil...

OK, Got the datalogging multi meter.

Got the card to hook it up to my array of inputs...
Threaded a ribbon cable to all the little posts... tested all the pins (beep... beep... beep goes the continuity tester!)

Now how to get the Ribbon cable to plug into my breadboard... Thought I had the requisite bits and bobs... But I left behind this at Frys...

because I did not yet see how it could be used to pull the even and the odd numbered pins to opposite sides of the trench in my bread board... You have to give it some rough treatment but...

 Clever! thanks Open Circuits!  Saved the day.

Tuesday, October 16, 2012

Gizmag is really easy to spoof...(evidently)

Sorry to have dropped away.    Thought I'd hop in with a quick observation:

I like to get the Gizmag emails with the wacky bikes and human powered helicopters etc... But along with comes the likes of this:

ARRG. I'll leave this to my kind readers as an exercise in critical thinking to see what is wrong with this product... (Not a hint exactly but an indication as to why you should sniff about before getting excited is the menu bar at the top: "Home, About Us, Investor") Watch the spinning wheel take people's money just like the ones at the roulette tables (minus the free drinks.)

Thursday, August 30, 2012

Maker Blocks

Somewhere out there in the blogisphere I came across a venture capitalist's blog posting about how he schedules time with his fundees. As a former startup founder he remembered the need for large unstructured/uninterrupted blocks of time for creative production. Scheduling meetings in the middle of the day for those sorts of folks is a killer as it punches a hole in a possible "maker block" of time. The day is shot as far as progress goes. So, short, late meetings or early meetings are the order of the day to keep large blocks possible for working.

(pauses to google up the posting - can't find it)

For me this was a great reality check and formalized what I'd been groping toward. Some work requires enough time to get into the flow, get out all the materials (virtual or real or the combination) and crank up the brain and then a period of doing, including failed experiments and then a wrap up/secure the winnings period.  The writer claimed that if you can't do all of that in one go, you won't get very far and should do something else with the time. I think he placed these lengths of useful creative time at 6 hrs minimum. I think 7 is more like it. The cool thing about this insight is that when you don't have that amount of time (for whatever reason) then you should not expect to get the new stuff done and should instead schedule "support" or "utility" work for those times and be happy with that. "Progress" is off the table until you can get a proper block of time. But when you have those blocks (they are hard for me to get) they need to be honored by delivering to that block of time a ready and willing brain. I can do that.

In some ways it is like the difference between quilting and draping. Draping needs a big contiguous bolt of fabric while quilting is built up from smaller bits.  Not a great analogy. But then I did not schedule 6 hrs for this blog posting. So there.

Tuesday, August 14, 2012

Time out for a motivational posting...

This guy is on to something.  I can't say I've made a study of failure, but the kinds of handicaps he is addressing sound pretty familiar (from both sides winning and not.) Vexing and familiar. But "know thy enemy" and all that.

Even the comments are pretty good (and the comments section there can get petty and political.)

Monday, August 13, 2012

Love Love Love online calculators

A number of years ago I was working on refinancing our mortgage and went hunting for mortgage calculators online to help me wrap my head around comparing offers. For me it was like having a fraction of a machine out on the bench so I could tug at parts and trace the wires and look back at the manual and really internalize how the bits interact.  A great exercise.

In that spirit if you are trying to understand Levelized Cost of Energy you could do worse than monkey with the calculator here:

Simple Levelised Cost of Energy Calculator at

Even the disclaimer at the top is informative:
Note that this does not include financing issues, discount issues, future replacement, or degradation costs. Each of these would need to be included for a thorough analysis.
(I might add salvage cost but that is a pretty good list.)

Let's take a look at some of the figures it integrates:

Capacity Factor: There is a link to a map and a less than graceful explanation of the CF. It is entered as a positive number. The pop up description says it is a fraction expressed in a decimal but you enter it in the calculator as a percentage. Anyhow, the idea is no system runs all the time at 100% so you need to factor that in. In the case of Solar that pesky sunset to sunrise period really packs a wallop on the Capacity Factor. Clouds too.

Today's Utility Rates: This does not take into account the tiered structure of most utility rates. Which is understandable as that alone would take ridiculous amounts of programing just to capture the inputs, let alone analysis. There are programs that do it but for simplification an average price of electricity will do.

Go monkey with that calculator and see what you think. If you know of another, add it in the comments.

What that calculator does not provide is insight into the Time Of Use values and Demand Charges which can play a serious role in the cost structure for large utility consumers. Modeling those is a much more case-specific task and requires extensive energy audits to generate the data to feed the evaluation.

Sunday, August 12, 2012

Forbes on Cogenra as seen by Vinod Khosla & Tony Blair

In the Forbes story about Khosla & Blair in the context of Cogenera a Concentrator hybrid.
Blair summed up Cogenra’s business strategy reasoning quite nicely: “People will not accept solutions to these things which mean that we can’t enjoy the benefits of modern living,” he told me. “And that is the key to unlocking the support of the people as well. People are very happy and prepared to use clean technology. But not if you tell them to do something that’s unrealistic for their life.”

To me this is one of the the two pincers that will drive the development of whatever will succeed in the solar biz: gotta let the consumer have more, better and for less (ideally both.) Just offering a green option is not enough to dominate. You get to participate, but not dominate.

In addition to the More for Less, anything new and expensive, really, really needs to land in the tax/finance/economic sweet-spot. I think Solar Hybrids are headed in the right direction as far as the technology supplying more for less (point one.) But the new, sophisticated finance approaches and better, more thoughtful and complete Levelised Cost of Energy calculations are coming along as well. That is not a simple matter and will, if we do it right, help to point out where the real value is. Finance, broadly conceived, is, I believe the second pincer - pressing us forward. It might be low-cost natural gas, low-cost flat plate collectors or even low interest rates driving money away from other investment vehicles an into energy hedging investments.

(Most of the finance sophistication is being soaked up into the utility-scale project teams and into the Power Purchase Agreements providers so they can figure out how to profit and how to communicate their offer to customers.)

This pair of forces can work together.  The desire for "more goods for less money" can move people to new behavior (a hard thing - people are hardwired to avoid making a lot of changes and decisions when staying pat is tolerable) but the new behavior has to be easily understood and well presented. Learning how to do that sales job is happening all over the place. Like SunRun, Solar City etc... more on them soon.

Maybe the next thing to talk about is the most famous hybrid: the Toyota Prius...

Saturday, August 11, 2012

Concentrating Photovoltaic Collectors - aka CPV reality checking

OK goofing off (by reading about the field so not really goofing off I suppose) and hit this tight little knot of information on the state of play in the Concentrating PV collector business.

Elsewhere I discussed the con artists that are working in the concentrator field but there are some legit players too, for sure. They might fail but it won't be because they are not really trying. The PV-Insider conference brought together a bunch of the real players in the CPV biz. I just played the recording of the CPV investors roundtable and the talk about the tax portion was amazing. The hurdles that project finance teams are going through is daunting. Makes me again worry about how big a part of our economy is taken up by finance. It is becoming a tail that wags the dog I fear.

Thursday, August 9, 2012

OK, OK I'm crushing on Cogenra's press staff

Maybe it is Vinod Kosla's press staff... but here is a fine article in Forbes about Mr Kosla's perspective and why he is investing in Cogenra ($10.5 million)

Short post. Gotta sleep. Tomorrow I'll show off the crazy box of springs.

Worthy Rivals Part Deux !

Check those guys out.   Unlike so many they seem to be pounding through the evolution stages from R&D to delivery and finance.

As you will eventually see, I'm not entirely crazy about driven cooling of the PV cells (but whatcha gonna do?) But if you set that aside they have a straightforward design and they have somethings lots of others seem to miss.

1) A target customer and they are driving directly at those customers: Commercial Accounts (get serious decision makers and big ticket orders)
2) Furthermore, Commercial Accounts that need lots of hot water for sanitation: Dairies, wineries, food processing plants.
3) Commercial accounts where land (aka Solar Aperture) is cheap.

BULLSEYE! There are plenty of those customers out there.

4) A major part of their plan (it seems) is to enter in Power Purchase Agreements (PPA) to take the financing problem out of the customer's to do list (and make money on the finance.)

These guys are putting systems in the ground for paying customers.  Bravo.

Take a close look at the various beauty shots of the collectors and tell me what you think. I see some expensive hand assembled gear (note the plumbing fittings for the PV's cooling jacket) built to take serious wind loads.  I also see light missing some of the PV (could be the photographer did not notice that they were unevenly illuminated.)

They have a video of the product intro at a winery complete with big time VIPs. The video does a good quick layout of the product/value on offer.

Best line is at 4:50 from Vinod Khosla (a very well respected Venture Capitalist.) "Nice that this is a technology that does not need a billion dollars in DOE loan guarantees to get started."

Really, go watch that video. That is the one with the most to chew on but there is plenty on that site to get excited about.  They have great press people too.

Full disclosure, they installed a system at Clover Dairy and I drink their milk - yummy cappuccinos, now with less greenhouse gas!

Thursday, August 2, 2012

OH (who are my readers?)

I started this as a notebook and a "keep myself going" exercise and now that there are a small number of readers I'm crazy curious as to who you are and how you got here. So? Comment already!

OK, the stats have some monkey business in them, looks like there are spam hits. How desperate for traffic must they be to come here to my tiny outpost, posing as a reader? Weird. Like power, when bots and traffic are cheap folks use them for stranger and stranger things.

Anyhow. If you are a real reader then hit me with a comment and tell me what you are seeing out there in the world of PVT hybrids.

Still more worthy hybrids and the logic of going large

Why aren't these guys making a bigger splash? 

I'm talking about: The Volther (now called simply the PV-T it seems) by Solimpeks. If you have a swimming pool these guys should have some of your money in their pocket.

Did you go and look at the presentation? Way deep in there (it is a long document but pretty good.) on pages 11 and 12 they layout the advantages of the superimposed approach they use. By having a front side of crystalline silicon sitting on a thermal collection panel they get to share the same aperture (my definition of a hybrid) and they share the support structure, the installation effort (mostly) and the "two" collectors can share the best spot on the roof.

Here are the advantages they list:
° Dual solar collection –2 usable energy outputs with one collection system.
° Improved PV generation–up to 50% more electricity than an equivalent conventional PV system with same peak output.
° Lower installation cost than an equivalent performance system comprised of a separate Solar PV and Solar thermal systems.
° Less roof space required than equivalent system comprised of a separate Solar PV and Solar thermal systems. In the UK this equates to approx 16m2 of PV-T panels compared to 25m2 of combined separate systems (21m2 PV and 4m2 solar thermal).
° Hybrid PV-T system’s ROI (Return On Investment) is shorter than standard PV systems due to higher electrical yield and off-set heating costs.
° Lifetime of PV cells is lengthened because cell operating temperature is reduced.
(That's pretty ugly formatting right there... sorry reader... but I wasn't sure you'd go to the site and pull down their presentation.)

Part of the trouble (the "why are these guys not making a bigger splash" issue) is natural gas prices, I know. But come on! This is sensible gear and a great way to hedge against rising fuel prices (they can't stay this low) and also a good way to maximize roof space use. Aperture (the amount of sun exposed property you have) is going to become a limiting factor as the panels become cheaper. Does that make sense?

This is worth thinking about. As the panels get cheaper and cheaper, the question changes from "how many can I afford" to "how many can I fit" and that is limited by the available aperture. Mostly this boils down to the roof size and any code limits on how much of your roof you can cover.

At that point you can't get more gear - so you need gear that can get more energy. That is the promise  hybrids offer.  Stay tuned!

Monday, July 30, 2012

More notable rivals...

Here is a paper on an approach to the degradation of amorphous silicon over time (the Staebler-Wronski effect) by a restorative annealing. Not sure how often those high but not crazy high temperatures can be accomplished just by stagnating the collector but these are early days in the research. It certainly is worth some research and is a creative response to the Staebler-Wronski effect and the need for high performance electrical and thermal performance.

I'm half way through the paper. Pretty well written too (as those things go.)


This is totally unrelated to my subject (hybrid Photovoltaic-Thermal solar collectors.) So if you are a purist just scroll to the next entry...

Mechanology (more stupid names for interesting products) is going through bankruptcy. Looks like a total liquidation as they have auctioned off their patents suite. I just happened to look them up today and saw that back on the 19th of July 2012 (just a couple of weeks ago as I write) they were putting all the gear and patents on the auction block. It seems they tried to sell themselves as a whole back in November of 2011 and it looks like that did not work.

I first learned about their Twin Intersecting Vane Machine back before 2000 I think. Certainly before 2003. The research was borne out of theoretical - seeming "pure mathematics" concerning toroidal geometry. Toroidal shapes are pretty interesting to me because they are DONUTS! I love, love, LOVE me some donuts. But in the hands of these Mechanology folks this same shaped space is occupied by a pair of vanes that, when spinning, create simultaneously a compression cycle (continuous) and an expansion cycle (also continuous) and to top it off: the ratios of expansion to compression can be different... All of this is a big deal.

For instance. The compression work done for a given amount of energy input was high enough for them to get a DOE grant to try to make them of plastic for fuel cell cars. Fuel cell cars for instance can get more energy from the same cell size (read same "weight") if they are run at higher pressures than atmospheric pressure. But these pressures come at the cost of the weight and energy appetite of the compressor.

But down the line, the real huge win could be a new format for an internal combustion engine. Imagine having a very efficient turbo charger on a rotary engine. But this rotary engine had an elastic power stroke that let it exhaust at nearly atmospheric pressure, in effect riding (extracting energy all the while) a larger fraction of the expansion cycle. They were years away from this but it was still a very interesting try. I thought.

I'll try to figure out what happened. Might be a classic "ran out of money" story. If the why is more interesting than that, I'll post it. Hey, if you bought the patents, let me know. I'd be curious to know what you are up to and if I can help.

OH BOY two blog post in a day. (you are welcome ;^) )

Prototype Work (or maximized minimalism)

Time out from the looking around at what others are up to. Since for the last couple of weeks I've had some time to advance on the prototype. YAY!

(Though, if you want to get a head-start on my review of the rivals check out:

The biggest issue for me is keeping the costs down but not being so thrifty that I quit (the cheapest option.) Running lean is one way to maintain an eye on the goal. EVERY item on the to do list is seen from the "how does this get me closer to the goal" stand point. Even the decision to make a prototype needed to be evaluated. "Running lean" is also a way to not let a venture like this one stink up the rest of your life.

I read a pretty good book on moving ideas into the marketplace a while back. "One Simple Idea." (I get no $ for that link and actually prefer to buy books from vendors that collect sales tax - to save me the hassle and 'cause it is more fair. But they are the easiest to link to and the reviews are useful.  A fight for another day I suppose.) The book is very good and has the advantage of being one of the few about product licensing aimed at individuals with new ideas. There was a lot of pent up demand and the usual invention books don't meet it. So good on Key (the author) for addressing it. Totally worth the price.  I have some reservations here and there but even the stuff I thought was off the mark was very much worth hearing his perspective on. He gives enough detail, as I recall, that you can draw different conclusions. I think of that as pretty rare (but then again I AM inclined to draw my own conclusions.)

So in that book he describes three different types of prototypes. Each has a use and a different cost to achieve. And he argues quite well that you should do just the minimum to get your product across and not waste effort and money on anything extra. In the licensing biz the licensee usually just needs to understand the product so depending on the context they might just need a compelling "looks like" prototype or mockup. The licensee usually knows more about how to make it than you, the inventor, do. So any effort to simulate their contribution (manufacturing and packaging) is not well spent. They just need to understand the new thing and the benefit it provides. Like a hurdler, we just need to clear that hurdle with the minimal energy so we can roll to the next hurdle and do the same.

The other two types after "looks like" are "works like" and then the dreaded "works like and looks like." I'm working on a "works like" because I'm pretty sure the illustrative/educational job needs to be done in 3D and some of the folks I'll be talking to would prefer to see it in material form rather than in computer simulation, where it behaved rather well ;^) . (How do we punctuate around emoticons?) My current theory about how the business side will go is that the prototype will open the door to more simulations. Which is good because my invention is a form factor and optimizing it really should be done in simulation where we can iterate fast. But for now a prototype is required, I think.

I called the "works like and looks like" prototype "dreaded" for good reason. If you find yourself doing one you better have good reasons because the expense is often enormous to make just a small number of anything (the whole point of mass production is to get the advantages of scale.) The more complex the item the more fiddly bits you'll be making in pricy small batches (or sourcing small batches.)  Key has what seems like good advice: never do a Works and Looks Like if another type will do. It is more efficient and shows your customer (in the licensee case) that you are in business mode and not wasting resources on unnecessary work.

So, as to keeping costs down, I'm building a test platform that should let me hook up and then tear-down the assembly safely and repeatedly for storage and improvements. The framework is wood, since I can work it easily with the tools at hand. Then for the other bits I am in perpetual "bodger-mode" (in the rough and ready, maker, sense.)

A good example of this bodger-mode, this weekend I grafted in a part from this type of clamp: Jorgensen hand screw.
I needed an adjustable sliding component. For $22, I got the drive screw (and a spare!)  The only tricky part then was finding a 15 mm drill bit on short notice... A call to Pastime Hardware in El Cerrito came up empty (a rare occurrence) BUT they referred me to Atalic Ace and suggested I check on 19/32nds as well. Bingo (meaning "Success!" for my non-native English readers) on both counts.

Some time with a paper model, some drawings (sketches really) and off to make sawdust! By 1:30 Sunday afternoon I had a working lift attached to the test bed and all for under $50 (yes it was an expensive drill bit! But now I know deep down that 19/32nds of an inch is darn close to 15mm and really, isn't the pursuit of knowledge what we are all about?!)

Remind me to tell y'all about how brake parts found their way into the prototype project as well.

OK next time a look at Cogenra and maybe Volther too...

Wednesday, July 25, 2012

Where was I?... Oh, yeah... Technolgy also rans

In the solar field there are a bunch of technologies coming and going.  Not just Solyndra but dozens of concerns rising and falling. For a while I tried to keep an eye on everything and I still try to skim publications to see what is being worried about and who's out front and the like.

But the deep reading has to be more limited. Hybrids. Photovoltaic-Thermal hybrids get the close readings here at camp Solar Spork. And some are pretty darn interesting I think. And I'm glad to not be alone in trying to accomplish a marriage between the electrical and heat requirements of buildings.  It would be a very alarming sign if no one else was working on it. So lets take a few postings to look at the current cast of characters. I guess these are not "also rans" but "also runnings" in that the race is still on. (I do have some interesting "did not finish" examples to share some time.)

(OH READERS? please do comment some time - this working alone can make it hard to know if one is making sense. Love to know how you came to this blog and what you are up to and the basis of your interest.)

First up:

They used to have a better name. This one just looses me. Anyhow, very interesting technology and they have some money and some early adopters and lots of data... Lots of what they have is not even their own gear just their assembly of same. So they put an array of PV panels and then ventilate the backs and draw that heated air into a heat exchanger for transport to a storage tank and or use in heating. Pretty good reporting on the performance to be found on their site. I wonder at their choice of date ranges:

Two sets of twenty systems each were analyzed to provide a robust sample size. Performance data from twenty systems was collected and analyzed for a ninety day period beginning January 1, 2011 and ending March 31 2011. Performance data from a separate twenty systems was collected and analyzed from the period March 1, 2011 to March 31, 2011.

This date range seems custom picked to flatter their system. To be fair, maybe this is the soonest they could start the study. They published it in June 2012 so maybe there is more to come? We'll see.

Still they are making the case pretty well and like other thermal players they are suffering the super low prices of natural gas.  Last year or so they were not talking about retrofit installations but the reality of the slow housing starts in the US seems to have given them the hint that the retrofit market needs some love.

Take a look and see what you think. Are they making the case for Hybrids? What makes sense in the way they put it and what should be clarified.

(These guys seem like the real deal - spending money and effort on the system and on making the case. Not just pimping a presentation and a prototype)
[edit note: fixed a bum link: 11/17/2014]

Head UP and Head DOWN

Part of "owning up" to being an inventor is learning a process that keeps doing a reality check. Over and over. Making sure you are working on a product that will likely have a use in the marketplace. The earlier you learn it will not go the more time and money you save. Some of it is guess work. But not all of it, and we can shift the odds by paying close and dispassionate attention to the marketplace.  Early and often.

I had a discussion with a guy who specialized in modeling the performance of solar systems a while back. He was a fierce skeptic about concentrator collectors. He thought the complexity of the tracking and the optical losses would never catchup with the head start given to flat plate collectors.  Interesting talk and I largely agreed. I think I have met most of his objections (I was not in a position to disclose, I just let him lay out his concerns and objections.)  It was a super helpful talk.

One of the things that lead me to was looking into the concentrator charlatans. I had seen a number of them on my earlier survey of the environment but had not thought they were anything but ambitious and misguided. It has been my practice to alternate between
1) looking around at the others in the field of concentrating and hybrid collectors.
2) minding just my work to get things done.

So on one of the "take a look around" periods... off deep in a discussion board I found a guy really making a pest of himself about an Australian concentrator company's claims about performance and an ever-slipping delivery date. Pest or not he was pointing out some all too familiar patterns. One prototype. Lots of investment news. Lots of distributorships sold. Few technical details. Then they vanish...

The question is: are they scamming just the investors or themselves and the investors or are they just a technology also-ran? It is hard to tell. In some ways it does not matter. The economic system (as it stands) needs everybody to try something and we let the market sort it out. But now I think a significant number are/were not trying to accomplish a new, more efficient solar collector but instead to take a good looking prototype and a slick pitch from would-be green investor to would-be green investor and take as much money from each as possible.

But where does that leave me? I'm not pitching investors so I guess that gets me off the scammer list. But that leaves me two other options: Scamming myself (blinded by pride) or a technological also-ran. Oh, I guess there is the "guy who figured it out" option too. Only one way to find out which of these three.

Charge on.

Fiddly Bits!

I decided to work on the prototype... Shoulda gone to Intersolar.

Plan B is to scan through the intersolar event website and see who was there and check out their websites. Working in the gap between solar PV and solar Thermal puts me in an odd spot market-wise. Lots of folks on the PV side have no clue about Thermal and the thermal folks are just spitting blood with the prices of natural gas so low.

Prototype blues: I need one way vacuum valves that can lock. Won't be needed in the real deal but my works like prototype needs them. So I get to work on weird tangents just to get through to the next "real" part of the work. Satisfying in some ways to make tons of dust and have a fiddly bit of metal to do the job result but also distracting in a bad way.

How to make it? I have two ideas (basically the same design with two ways to achieve it.

1: Drill press method. roughly machine some small plates and bolt them together.

2: Lathe method. Design a bunch of concentric holes. Tap the smallest for the lockigng screw and stack the components in there and then we are off to the races.

Method #2 means dragooning a neighbor into lending some lathe experience and time.

Method #1 takes lots of trial and error.

ONWARD and DOWNWARD (into the weeds this week)

Tuesday, July 10, 2012

Intersolar is happening in San Francisco this week.

I went last year and learned A LOT:

About the business climate.
About how the current manufacturers see themselves in the solar panel eco-system.
About how pressed the manufacturers are on costs as the prices continued to crash.

There were even some folks showing hybrid photovoltaic thermal solutions. (the very subject eventually, I promise, of this blog.)

I was carrying around a copy of my white paper on my research into a high temperature hybrid design and how high temperatures are possible and why they are desirable. I handed off a few. I wrote a bunch of follow-up emails. NOTHING.

well. almost nothing.  (spoiler alert: moral of this post? write thank yous TO EVERYBODY! EVERYBODY means everybody)

One came back with a big big clue as to where I might peddle my wares. For now lets just say "not solar energy companies." They have clamped their jaws around flat panel collectors and are riding the cost curve to the ground (the metaphor mixer is in fine shape dontcha think?) Most of the novelty in that business is directed at coming closer to the approximately 24% theoretical limit, shaving costs and economic/finance manipulations to make the market soak up and adopt solar systems faster. That and long shot plays in thin films and novel alternatives to Silicon. Not efforts to thumb one's nose at.

So I got no takers on "can we talk about research?" but a good bunch of practice on quickly outlining what I am up to.

Do I go back? Or finally put some fresh time in on the prototype? Stay Tuned.
Did you check out the cool roof project mentioned in the last post? I came across it quite a while back when I had an idea about using pigments like the color shifting cars to give roofs two different looks, one to the Sun and one to the ground. The pigment systems turn out to be too expensive to use in roofing where CHEAP rules. If you have priced roofing you'll say it is not cheap but on a per pound and per square foot basis it _is_ cheap. That business depends on low cost inputs, the pigments binders and fibers all have to be cheap and durable so you can afford to use lots of it and still pay for all the labor involved in installing it. It was an interesting lesson in manufacturing costs for me.

Anyhow. The idea of a roof looking one way to the sun and another to the passers by is pretty compelling even if the color shifting system cannot be applied. The idea was that for the direct light of the sun (the primary lighting on the roof) is for the most part not bounced to our eyes. Most of it is absorbed and or reflected elsewhere. The absorbed bit during the summer is the worrisome bit. All that heat... Thus the silver roofing in places where we cannot see the roof. Silver paint is pretty ugly and buildings do have to keep up appearances.

OH, a neat story I think I read in Amory Lovin's Natural Capitalism about a building superintendent who, once he learned about cool roofs and had some tie to the cost (I forget how he was incentiveizd) made it a practice to mop the silver roof to keep the absorptive dust down to a minimum. This tiny act took a part of a morning and paid off over and over in a big way in reduced energy costs. One morning and a bucket of mop water.

Funny book that, full of adoration for what turned out to be the fraudulent Enron and for a long while the website of the book stood like a ghost town. (I took a look for it again and the participation part where passersby could tease them about the Enron bits was not there anymore.)  But the book is not all bunk. Lots of interesting systems thinking and reminders about how misaligned the incentives are in so many economic relationships and energy systems.

Ok... this has been sitting in the draft folder too long.  More soon.

Tuesday, June 5, 2012

Lazy Roofs

I've long enjoyed climbing on roofs. I don't like the edges and ladders are not loads of fun but I am drawn to the roof anyhow. You can see a lot, of course. More sky usually and you are also invisible to a great number of people walking by who do not look up. Which is interesting. To me at least.

I've wanted to make roofs more useful for a long time. Maybe I am insufficiently grateful for protection from rain and the containment of warmth.  But for as long as I can remember, it seemed to me that they could do more. For a while, I wondered if we might not productively require greenhouse space or water collection to reduce the waste of space that roofs represent. Solar is another solution but there are some very inexpensive things like water collection and skylights that can contribute to the building's utility in lasting ways. The cool roof, for instance, involves picking roofing materials with an eye toward its reflectivity across various spectra and their ability to re-emit energy back to the sky. Small differences in material choices, often with no associated cost penalty, can make a big difference in the optical and thermal performance of the material and thus the building. These are the low hanging fruit.

Solar systems are much more expensive but they can earn rather than just save.

Tuesday, May 29, 2012

more reservations (part 3 "subsidy surfing")

So I'm stalling out, right? I could afford the proposed system (lucky) and I happened to have the cash at the time (way lucky - we'll take up this "financial-ization" of the solar biz later I promise.) But my side questions were getting in the way of, "yes."

I also hate waste of all sorts. The idea of surface area that could be used being left out worried me. As does not getting the most out of a visit to the roof. Cranking up a project on the roof is dangerous and expensive (relative to doing nothing - which is an option.) Also, so much of the cost is labor and just getting folks to the site. Add to that the fixed project management costs and it seems a waste to install anything less than the maximum system. If we get the maximum system we can spread those costs across the most productive system. Seen from this perspective the roof needs the maximal coverage to get the costs down.

But this is not how the estimators see it. And they are right. Back then (and this is a moving target) the goal was not to put the maximal system in but instead to ride the cost curves accurately by not over building. The big cost factor that is not addressed in my little optimizing discussion in the preceding paragraph is "Tiered Billing." I have a fairly thrifty lifestyle relative to most Americans and live in a mild climate (lucky again) and this has particular impacts on my electricity bill. But the biggest impact comes from the tiered system of billing. The idea of the regulation is (I surmise) to keep the cost of electrification low for the modest users and charge more for customers who use more (and can afford it more easily.) So the first few thousand watts usage a month are cheaper than the subsequent thousands. In California it is based on a fairly complex system of average daily use for your zone (mostly about climate)  for a home of your size and kind.  If you like rabbit holes of regulatory complexity... take a look at how this sausage is made. Yikes.

The boil-down (you are welcome) is this: Solar panels, cheap as they were, were still, all told, unable to match the price of the first couple of tiers of electrical pricing. So the smart estimators instead plan to offer you a system geared to replace your later, more expensive tiers of electricity. Those later tiers solar can compete with... So you get a lower electricity bill and a solar system.

One more complexity is the crazy shifting incentives program. I say crazy but it does have a logic. The state of California has a per thousand watt incentive program that phases out slowly as a way to wean the market from the subsidy. Smart. It provides some urgency and motivates folks. At the same time the cost of panels and other elements have been dropping so figuring out the way prices are going is tricky work.

But back to our story. The salesperson proposed a layout based on the system suggested and had no provisions for adding more later. This is, again, reasonable from the most common perspective which boils down to return on investment (setting aside all other concerns.) But I, of course, have other concerns. Like keeping room for thermal somewhere and future expansion and denying bankers a cut. I know we pay them great sums of money as a society because the work is so hazardous and unpleasant. But we have established that I am a jerk in some contexts and here is one: I don't like bankers and the outsized role they've taken in the economy.

Looking at the plan I suggested a different orientation for the panels and some racks that would be installed and not used, yet.  The idea being to not waste space by inefficient tiling of the panels and toe not waste trips by workers to the roof by getting the maximal amount of racking installed as one project and the maximum number of panels I could afford today. Then as my electrical savings change the cash flow story and as panel prices come down (which they did) I could add more panels. This did require using different inverters (so called mini-inverters.) My theory was I could offer the installer a deal: Fill in the remaining spots in the rack a couple at a time every quarter at your leisure. Get a spare half day with a crew or need to do some training or want to push some panel order up to the next price break level... add mine and keep your savings on all of them. I'm in no rush. The longer I wait the better the panels and the lower the price.

Now there are plenty of fine reasons to say, "no" to my plan (even "don't wanna" is a fine reason.) But my salesperson thought I was trying to work the subsidy program. The assumption was that I was trying to maximize that end of things. It would not surprise me if that was the primary motivating factor in many customer's reasoning. But not mine. I was told, "If you want to fool around with the rebate calculator I can point you to it online, but I can't go back and forth on this, it takes too much of my time." (That is a paraphrase - I just reread the email to check my understanding, that was a mistake - I was offended all over again.)  I wrote back trying to clarify that mine was a "yes and" rather than a "why can't I?" exchange, but I never got a response.

So, I'm one that got away. The solar business is going gang busters so frustrating folks like me is not a problem for the industry... But these issues started me on the path I'm now on and I am trying to keep fresh the memory of my "novice mind," which should come in handy soon.... more on that later.

Next up. Lazy roofs!

Thursday, May 24, 2012

more reservations (part 2 - blackouts)

Still working through the list of questions and concerns raised by the proposal for rooftop solar.... Next Up? Why can't a guy (or a gal, or a group of guys/gals in any combination for that matter) use the electricity from the panels during a blackout?

This is not important. Really. I don't have medical equipment or other life critical loads. I just needed, way down deep in my "check to see if you are dealing with folks who really know their stuff" brain, to know why the electricity generated needs to go to the grid first and then come back rather than stop here at the house first if I need it and then join the grid if I don't need it.  This conception, I hope you gathered from context, is wrong. It makes intuitive sense - but it can't work that way with current technology.  I know that now (and will endeavor to explain it to you my kind reader in a moment.) But for now lets address the sales communication issue: the customer (me sitting with my checkbook) wants something, thinks it is possible and you cannot (nor can anyone else) deliver it. What do you do when faced with these questions? Well if you want one of those checks, you don't dodge the question, you address it.

Maybe I am a jerk (OK, I am certainly a jerk in some contexts) but, if you can't answer questions about how this stuff works (and does not work) you and your buddies don't get to put high voltage gear on my wooden house filled with my flammable family. For any price.

This question about why a photovoltaic array was not able to stand as backup power in emergencies was also a, "let me see if I (and you) understand (each other)" sort of question. I like that sort of question because I often uncover non-obvious misunderstandings this way. One just restates the thing.  Does it still works in different words? Or does that restating flush-out some unstated exception, or remind the interviewee of some detail.  Somewhere along the line I developed the habit and it has left me in very good stead.

Are you still wondering why we cannot use the electricity from the panels in a blackout? A couple of things make it too complicated and expensive and dangerous to do it. First off, the electricity needs to be converted to alternating current (AC) from the direct current that is created by the photovoltaic materials if it is to be used by your appliances or put on the grid. If you had some batteries (direct current) and/or some appliances that run on DC you'd be good to go in the blackout. But most of us don't get blackouts often enough to justify having all that expensive gear just for the once every few year blip in the power supply. So in the place of a battery (which can be thought of as a TIVO for energy - the energy comes when it does and comes out when you need it) you use the electrical grid. The grid functions as a super cheap battery if it is already available. One of the tricky bits in this "putting it onto the grid" business is timing the too and fro of the alternating pulse (at 60 hertz* in the US and other rates elsewhere) so that rather than cancelling out the energy you add to it. Grid-tie inverters do just this: the convert (invert) the DC to AC and pay out the AC at a rate that matches the frequency of the grid.

Imagine kids jumping a long shared rope. The rope has a pace and to get in and join the jump you'll need to watch and get a sense of it before you jump in or you'll mess it up for everybody. With the grid, you need the energy you add to the grid to alternate at the same rate and in the same phase as the larger system. In this way you can add to the energy stream. If you don't, you'll be a load for the system rather than a source. For this to work the inverter is built to be a follower of the dominant signal from the grid so it can hop in and join rather than go it alone. The danger in trying to lead rather than follow is when the grid is down... you end up "back feeding" the grid. When line-workers are out restoring power, the last thing they need is energy coming "back" from "down stream." Ouch.

The electrical grid and the wiring of your house are also based on a super abundance model. There are breakers and fuses to protect against too much power. But the case of too little power is weird. Unlike you body, which will reroute blood to vital organs at the cost of peripheral body parts in a shortage, the electrical system of your house will give every appliance as much as it asks for. Even if there is a shortage of electricity, as long as it is beneath the maximum limit of the circuit breaker each item that is turned on can take what it likes. This can lead to all kinds of squirrely (is so a word) behavior.

In theory, we could have house wiring systems that divvy up power for higher uses (like your kegerator or iron lung) first. And we do have some protections in place for hospitals - for instance the grid managers try to hold them out of rolling brownouts. OH and hospitals have generators too. But, in general, when the demand outstrips supply, there is a need to shut down parts of the grid to get demand below supply. The same is true for your house. But constantly watching the supply and shutting down circuits is expensive and complicated stuff for spaceships and submarines and such. Instead we just try to keep ahead of demand by predicting how much will be needed and in what increments it might spontaneously grow and where and then run the supply in anticipation of those needs.

In the commercial energy world (like running your big box retail store) there is something called demand priceing that measures the sorts of jumps in power demand you might put on to the grid all at once. They charge you to have that amount standing in reserve. It is expensive and has lead to some smart demand management systems that pay for themselves in short order as they save on these demand fees. Things like spinning up air-conditioning units one at a time or in small groups rather than all at once.  Same with factory floor equipment.

Anyhow, standing alone as an energy producer is one task, participating in the grid is another, and jumping from one to the other on the fly is tricky (read expensive.) But not as expensive as having a customer stall out because you have not established trust.

So on to subsidy surfing...

*(named after Heinrich Rudolf Hertz - still more proof that all the good units of measure are taken!)

Thursday, May 10, 2012

more reservations (part 1, no thermal?)

Other things about the proposal were not on the page but still gave me pause...  No place for thermal collection. Huge fractions of the energy used by a home are thermal. That's why moves like wrapping your hot water heater are such winners. When the numbers are big small percentage gains are still worthwhile.... Anyhow. The proposal was just for photovoltaic panels - so only for electricity... I guess hoping for a thermal component in the proposal is a bit much. Kind of like expecting a plastic surgeon to suggest getting some sleep. You might need some sleep - it could even help with the bags under the eyes but if you have a box of sharp knives everything looks like a knife problem.

Where was I.... THERMAL. Yeah.  Along with a different skill set (electricians vs plumbers) there is the new problem of very very cheap natural gas around here. Used to be your payback period (I'll rant on that bankrupt idea some other time) was something like 5 years. Now the gear is still about the same but the cost it is competing with (natural gas) is going down. But still, if you want to knock down your carbon footprint solar hot water is a great way to go and it is a fine use for part of the roof with less good exposure. ¿Less good? (Oy, does a blog instantly make you a language slob?)

So solar now seems to mean PV first and nothing else second. And not seeing hot water on the proposal slowed me down.  But for me, once you start climbing on the roof and poking holes you should do all the work at once, no?  Next up: Blackouts.

and so it began

Back in the summer of 2008 I got an estimate or solar panels for the house. Seemed reasonable. Our house is older so the roof could use some more beef before it could take the load but nothing crazy. I read through the estimate and saw this:

De-rating... is... a... bummer... 

But it is not BS.  Those factors really do run down the performance of a solar module and a system overall. The two that really leaped out at me were the temperature and the conversion losses.  Let's call them the "ugly 80's." Now I was not  interested in batteries so it was just an academic interest that drew me to the .86 de-rate factor over there, but the temperature de-rate really hurts (these are cumulative.)  I joked with the estimator that we should install them on the garage to take advantage of the shade there. She was not amused. 

Three more things about the estimate bugged me... thermal, blackouts, and subsidy surfing. More on that next time.