Monthly Archives: March 2013

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Ammoniak en Fijnstof afvangen

Fijnstof en Ammoniak zijn schadelijk voor de gezondheid. De landbouw (voornamelijk varkens en kippenhouders) veroorzaakt ammoniak emissies die ver boven de Europese norm liggen (Joel Salatin laat zien dat deze dieren veel beter de ruimte gegeven kan worden). De manier om ammoniak af te vangen is door middel van een waterdouche, het wassen, iets dat in de industrie op grote schaal gebeurt als het gaat om zwavel bijvoorbeeld. Fijnstof wordt het best gefilterd met een electrostatische filter, waarin deeltjes een lading wordt gegeven zodat ze uit de luchtstroom kunnen worden getrokken door een electrode met tegengestelde lading. Bob van Usem laat zien dat met een combinatie van deze twee technieken, geladen waterdeeltjes, een zeer effectieve filter gemaakt kan worden.

Deze ontwikkeling is interessant, omdat ammoniak een ongebruikte energiebron van formaat is. Het is een stikstof-waterstof verbinding die in planten de energie levert om de groeien, maar die wanneer de waterstof via een catalysator wordt vrijgemaakt ook in een brandstofcel te gebruiken is. Het ammoniak emissie probleem is een enorme verspilling van energie. We hebben hier al eerder over ammoniak geschreven, het zou ideaal zijn om zonder veel aanpassingen landbouwwerktuigen mee aan te drijven.

Zie ook www.greengas.cc en Zelf ammoniak maken  De ontwikkeling waar de boer hierboven over praat wordt voornamelijk tegengehouden zodat de boeren geen macht krijgen. Dat is noodzakelijk om de fossiele consumptie economie in gang te houden.

Fijnstof

Fijnstof afvangen met een electrostatische waterdouche is misschien een optie voor scholen en grote gebouwen waar kinderen lang moeten verblijven. De fossiele lobby pushed de snelheidslimieten vlak bij de bebouwde kom omhoog voor meer inkomsten, maar dit gaat duidelijk ten koste van de luchtkwaliteit. Fijnstof van fossiele emissies kosten jaarlijks honderdduizenden levens (ook door bv. Ozon). Een installatie zoals in de bovenste video beschreven zou op zonnepanelen kunnen draaien, en lucht direct vanuit een met geluidsbarrieres ingebouwd snelweg traject kunnen afvoeren en zuiveren.

Protest tegen fijnstof (van Max80.nl) veroorzaakt door de A10 en A13 bij Overschie op het Plein in Den Haag. Misschien kan een soortgelijke scrubber als in de bovenste video beschreven wordt zorgen voor directe filtering van fossiele emissies.

Naaldbomen halen voeding uit deeltjes in de lucht die aan de naalden blijven kleven, en zijn dus goede fijnstof filters.

Mos kan fijnstof filteren als het nat is. Lara Smits heeft een mooie demonstratie locatie gebouwd.

Heggen van naaldbomen hebben een goed effect, zoals in de proeven met een electrostatische filter van Bob Ursem is te lezen. 

Uit onderzoek naar mossen en fijn stof is gebleken dat één vierkante meter mos per jaar zo’n twintig gram fijn stof kan ‘opeten’. Valt de fijn stof op het mos, dan houdt de plant het vast en voedt zich ermee. (bron)

In een onderzoek naar fijnstof in kinderdagverblijven werd een positief effect gehaald met de Aspra filters, een verlaging van 85% fijnstof tov de buitenlucht. De geteste filter is bovendien energie zuiniger.

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A Climate Solution

It turns out that cattle has a symbiosis with land, just like Joel Salatin already demonstrated on his Polyface Farm, meaning desert land can be reclaimed by grazing it with carefully managed herds of cattle. Using this strategy it seems we can really return our atmosphere to pre industrial CO2 levels.


Doing this would require some kind of herd management device, probably a digital solar driven device that can be used to keep herds in certain places, for lack of electrical fencing (as Joel Salatin uses).

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De Fossiele Financiele Zeepbel, of Productie Sinkhole?

De Volkskrant heeft een stuk waarin wordt gesteld dat wanneer de fossiele sector zijn grondstof in de aarde moet laten, om meer CO2 uitstoot te voorkomen, dit betekent dat de waarde van de reserves zal instorten. 

"Als het hooguit 2 graden warmer mag worden, dan mag er niet veel CO2 meer in de atmosfeer komen. Dat betekent dat het overgrote deel van de gevonden fossiele voorraden niet mag worden verbrand, en dat gaat de eigenaren van deze reserves geld kosten."

Fout. Het niet mogen verkopen van de fossiele brandstoffen kost de eigenaren geen geld. Wat het wel doet is de noodzaak geld te creeren verkleinen, omdat er natuurlijk minder geproduceerd kan worden, omdat er minder brandstof en producten verhandeld kunnen worden. De afname van brandstof aanbod zal zorgen voor inflatie zolang de banken niet tegelijktijdig krediet intrekken zoals ze nu doen (vanwege een slinkend fossiele energie aanbod!).

De hoeveelheid geld is arbitrair (wordt door banken bepaald), de waarde van geld hangt (nog) af van de hoeveelheid fossiele brandstof die op de markt komt, en hoeveel daarvan wordt gebruikt om welvaartvergrotende producten te produceren.

Simple divestment in fossiel ook omwille van een reserve zeepbel (al dan niet opgelegd) helpt niet omdat fossiele bedrijven geen geld nodig hebben. Olie wordt niet met briefjes van 50,- Euro gewonnen, maar met olie, kolen, gas en machines die op die energiebronnen draaien. De investering in fossiel is slechts om het publiek de indruk te geven dat geld waarde heeft onafhankelijk van fossiele brandstoffen. Wie dat probeert te bewijzen faalt.

If oil stops, production stops. Do you want to wait for it?

Als de fossiele sector opeens zou aankondigen dat ze minder hebben dan geclaimd (wat gezien piek olie in 2005 niet onaanemelijk is) dan zal dit ze niet raken, ze kunnen gewoon doorgaan met het verkopen van wat ze nog wel kwijt kunnen. Er zal een transitie naar gas en kolen worden voorgesteld. Het zal een debacle zijn als we het aan de sector zelf overlaten. Opeens zitten we zonder energie om een transitie naar schone energie te faciliteren (ook al kunnen we daar ook hernieuwbare energie voor gebruiken).

Zie "The carbon credit system, a limit to growth"

In plaats van de focus op de financiele kant, de fossiele reserve zeepbel en financiele administratie van de verdeling van brandstoffen moeten we ons afvragen hoe om te gaan met de productie ‘Sinkhole’ die het plots wegvallen van fossiele energie met zich meebrengt, extreme inflatie, werkeloosheid, honger, dood en chaos. In plaats van een reductie van productie te ondervinden zoals we nu doen, ijverig de nieuwsberichtjes lezend van Shell en Exxon, Gazprom etc. moet hier proactief mee worden omgegaan. Wat over is moet worden geconfisceerd en gericht worden aangewend voor het creeren van een productieketen voor hernieuwbare energie bronnen al la WOII wapenproductie.

Oil sector autonomy enables a war against humanity 

Consumptie van fossiel moet streng aan banden worden gelegd. De ‘vrije markt’ die nu dient om zoveel mogelijk fossiel te verspillen moet omslaan in een werkelijk vrije markt voor hernieuwbaar en wat mensen daarmee produceren in combinatie met een streng gereguleerde markt voor fossiel, zodat geen druppel wordt verspild. Tot er genoeg vloeibare brandstoffen, gas, ethanol, ammoniak op basis van solar en wind worden geproduceert, en dan kunnen alle fossiele bronnen dicht.

Shell produceert een zeer ecologisch zonnepaneel (Solar Frontier). Opschalen die hap! 

Beter zou het zijn als alle fossiele producenten bij elkaar kwamen en de dreiging tov de mensheid in acht nemend een plan smeedden dat transparant gericht is op het zo snel en efficient mogelijk uitfaseren van fossiel. Niemand is bij meer fossiele uitstoot gebaad, iedereen kan bergrijpen dat hernieuwbare energie dezelfde welvaart (zo niet een veel grotere) biedt. Goedschiks of kwaadschiks, de landen die getroffen zullen worden in geval van een plotselinge terugval van fossiele energie zijn het zichzelf verplicht maatregelen te treffen, en deze landen zullen het eerst de veel grotere duurzame welvaart proeven dan degene die zich laten vangen in een fossiele sterfhuisconstructie. 

Voor een masterplan zie Euro, Auro, Joule

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The BBQ on the Powerkeg or how Renewables are Going to Blow!

Our world exists on the cusp of a positive explosion of wealth. Like a powderkeg used to support a BBQ it’s gonna blow, against the trends. The reason is simple : Renewables can build renewables.

Oil wells don’t spring forth oil wells, nor do gas wells or coal mines. Renewable energy sources can produce renewable energy sources. All you need is raw materials and energy, and we have plenty of those.

We’re burning up 

The vision of the future is bright, and considering the fact our sun hands us about 5900 times the energy annually as we have as fossil reseves in total we really should question our willingness to even consider using them. Once you transition you don’t have to ever go back, ever. Modern humanity can settle supported by renewable based renewables, automatically manufactured to replace itself, into perpetuity while restoring our planet for the lifeforms we’re familiar with..

Carbon has devestating competition. Elbow from the sky! 

The battle is between those that believe in economics, a philosophy designed for an imaginary world with infinite resources, and those that believe that we can live prosperously without being a burden on our planet, those that understand the premises of ‘Roboeconomics‘. Scarcity is a choice if you have the help of automated machines that can run entire farms and factories powered by renewables. Scarcity is what our present economic system depends on for it’s existence.

The hydrogen fusion reactor in the sky has infinite patience… But how about you? 

How are we hindered in achieving the vision? The following elements are essential for our detention :

1. A credit based financial system, that depends on fossil fuels to make it’s credit worth something.

2. A banking system that blocks wealth creation except when it is fossil fuel based and debt loaded to ensure it does not become a competitor.

3. Markets owned by banks, so they can ensure nothing enters it that affects their power and prices are favourable to some but not to others.

3. A intellectual property legal framework that allows occupation of trivial ideas and images, thus handing control over the psyche of billions and creating a uniform culture dominated by a few ‘celebrities’.

4. Physical separation of production and demand. Food produced far away, to ensure both the inability to compete locally and the extraction of cash to create demand for credit and force people to ‘work’ for money. 

Weird absence of economic activity 

You never see to much activity in desert areas. While the sun beams down massive amounts of energy there that could spawn all kinds of wealth. Our carboncredit economic system can’t utilize that energy, because it would not be able to control or own the wealth and so it inhibits it’s exploitation. Could Europe produce massive amounts of ammonia fuel (NH3) to power logistics and cars in the Morrocan desert? It could. But who would be dealing HN3 credit? It would have to be the producers! Who would be wealthy like oil sheiks? It would be the owners of the solar thermal NH3 factory (or wind as was done before).

It can be done with private funds in relative secrecy, the creation of self perpetuating renewable powered sources of food, water, solar panels, fuel. Those sources would make massive and continuous profits, force banks to extend credit without gaining any power, the power would remain with those that produced based 100% on renewables.

The final correction would come as the producers would start extending credit themselves. Ultimately this power base would also take a backseat. Most people would be well off, and some rediculously well off. Today due to the scarce nature of the powerbase (fossil fuel), most people are expected to be miserable while some will be very well off.

Of course you, in your insulated home with energy source to ensure comfortable living, would also have something to trade at times. Your renewable addition would be like the farmer’s food brought to the markt, a value to him, not to any bank. This shows how much different the renewable based ‘economy’ is from the present one. To get there we need more renewables, we need to ask for them, demand them and build them where we can. We also need to break down the obstructions mentioned above, most notably the free fossil fuel market. Autonomy of fossil fuel exploration and trade has to stop, because the more energy can be directed to wards renewables, the quicker we can start building them without fossil fuels. As a result the financial sector will become irrelevant. What use is it to create credit if the recipient can’t go out, buy fuel and do whatever they want with it.

To speed up this process we can create extraeconomical zones, and a program to develop them. A good place to start would be the North African Desert, Lybia, Morocco, Tunesia, Egyptor the Arabian peninsula. 

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The Grid : Between a Rock and a Hard Place

 “The secret of change is to focus all of your energy not on fighting the old, but on building the new.”—Socrates

Our position is to promote renewables first, not efficiency, because then the resto of the clean energy transition will follow. We are confirmed in this conviction by the changing situation in the energy markets.

The Grid to consolidate legacy energy?

Previously we worried a lot about the smart grid, in every size and shape, because it really is a waste of energy if you compare it to using the same resources for building renewable energy generators. The Grid is promoted using a distorted reality of a world with a highly dynamic energy market and super intermittent unreliable renewable sources and no place to store any of the peak or surplus production, at least not at ‘reasonable cost’. This artificial situation however can not withstand the effects of increasing renewable capacity, and here’s why.

Negative prices? Compare Germany with France

Even though the Grid is proposed to serve transportation of coal, gas, nuclear electricity, it also transports renewable energy. This means that energy enters the market around Europe. This means it competes with fossil energy, seriously competes. Yesterday German Wind electricity had a negative price, minus 80,- Euro per MWh. Compare this to the cost of electricity in France, around 57,- Euro per MWh. So Grid expansion will lead to increased competition from renewable sources, a better carbon offset scheme than the virtual one we have now.

This trend does not play well with the economics of running wind farms, but economics doesn’t do that in general. In economics all resources are priced first, then the money to buy them is extended as credit. Renewable energy creates the right to extend energy credit, by the energy producer outside the economic/banking system. It requires a new credit system to free up renewables to their full economic potential, but even without that, they push out and shut down fossil generation. The Grid helps renewables, it does not protect legacy energy producers!

"Renewables need flexible backup, not baseload" 

Embracing Storage?  

So while the legacy producers are lying about the need for a grid and the impossibility of storage, their strategy (grid expansion) doesn’t help them in any other way then diverting resources away from renewables. The real killer though is storage. Take that intermittend wind power and solar and shift it a couple of hourse using any type of storage, and grid investment becomes unjustifiable. Solar panels are autonomous things, batteries can be the same, both can keep a household running even through the winter.

Battery technology is kept expensive and utility scale, but you got so much types, like NiFe NiZinc, Active carbon ultracapacitors, Liquid salt, AluminiumAir, even ordinary lead Acid. Usually already up and running in industry for decades. To keep them expensive banks invest millions in them, hoard patents and push up the price. Even the very inefficient concept of hydrogen storage, requiring some nickel, tubes and graphite and a plastic membrane with KoH in it costs thousands of Euro’s after decades of production. 

Business cases for storage will start to make more sense the more renewable energy is produced and peaks simultaneously. But it really takes a reset of patent law and financing regulations to force the obvious switch to local storage with long range replenisment through the grid. This can be augmented with liquid fuel generation based on renewables like ethanol , NH3 (ammonia) and other fuels (as pioneered by the US Navy). 

Win Win 

Either way, a win win situation is developing. The grid does not protect centralized power generation, and motivates implementation of storage. The centralized generators can’t win. The economic power of renewables is growing palpably. So the strategy to support more renewable energy sources remains the most effective one to defeat fossil fuel/nuclear.

See also : The Carboncredit system : A limit to growth 

The Euro, Auro and the Joule

Roboeconomics 

Please donate! 

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Last Warning : UK’s Gas Sensitivity

"Energy giant Centrica threatened to quit its North Sea operations today over an increase in the corporation tax rate." (bron)

A while back several gas companies threatened to close North Sea gas wells when the British parlaiment suggested it would tax (take) more of the gas produced. In the mean time battle ships sailed to the Falklands to exersize rights over the oil under the island group (and the area around it, because you can drill horizontally).Argentinia didn’t want to hear of it and send the Brits away.

Today : UK Gas prices soar as pipeline is shut down 

The problem with our modern fossil fuel dependent weapons technology is that you can’t use it to conquer carbon reserves if you run short. The country protecting the reserves usually has more and can project more damage than you. So like a starved lion, at a certain point you are to weak to kill anything anymore, and you starve to death. This creates a now or never mentality when it comes to retaining carbon age dominance by both the UK, US and other states. At the same time cooperating states will free up fossil fuels from any adversary that does not have allies it shares its reserves with (like Iraq and Lybia, Iran).

Today : 36 Hours of Gas left in UK 

A case for Wind Heating Systems for sure. Help us build one. But in reality if gas does run out, and supplies get diverted, stopped, sabotaged etc. we will see the first of many fossil fuel shutdown panics to come. People will freeze to death. The trouble for the UK is that if it’s financial hub of London loses it’s power due to the many frauds revealed the island really has little to trade with, and will need to take care of itself. As we said before trying to transition away from fossil fuels while you have none left is the most impossible thing to do. 

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Global meat farming policy : Use grass

The meat industry is a major contributor to greenhouse gas emissions. Not only of CO2 but many others related to the activities necessary to farm animals intensively. From raised rainforests, the long range logistics of GMO soy in South Africa to feed cattle in industrial farms in Europe. Soot, NOx, VOC, methane, ozone the range of damaging compounds is endless. The main reason for this is protection of cashflow in the carboncredit system, the system that tries to utlize as much fossil fuel as possible.

Devestaring and unnecessary GMO soy farming 

The point of meat farming is to get animals to eat a lot, so they grow big and strong with lots of muscle, so that when slaughtered they produce a lot of meat. The idea that this is best achieved by feeding them simple diets, antibiotics and cramming them in a small space during their entire life may be a result of the incremental nature of improving production. Another factor determining the design of industrial meat farms is economic ‘loading’, meaning many parties want to be invloved in the proces, whether they are usefull or not.

Running into the dead end of incremental carbon fuel based ‘optimization’ 

The party for animals in Holland has placed animals in the forefront, redefining the challenge of farming to think from the perspective of animals instead of the end product or economic volume. If slave trade had never happened we would probably all believe animals feel and experience pain just like us. But because slaves had to be non human to be traded the idea animals did not have consciousness was taken as fact.

Joel Salatin shows how you can produce meat on a grass and grain diet. The grass is grown without tillage, plowing, and actually consists of many species of plants that together form a tasty snack for the animals. His farm model does have stables, but only for the wintertime, not as a kind of metal strait jacked in which animals are forced to grow. The carbon emissions are much less, and the soil actually accumulates carbon year on year. 

Grass based farming with organic grain feedstock could have a negative carbon footprint.

Salatins farming method combines species on the same grass, chicken and cows, piggs in the forrest, which has the advantage that pathogens run into dead ends (and have a hard time anyway because they are mostly outside).

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Building a Wind Heating System

Fund our development by sending some cash to paypall info@climatebabes.com and follow @climatebabes on Twitter.com..

Also see :

Wind Heating System Patents and Open Design Project 

Apple Stole Our Idea! Using Wind to generate Heat! 

Open Source Research in Wind to Heat Conversion 

We need funds to build a wind heating system demo. The concept is very simple, it has been picked up in a number of patents in recent years : You convert wind to heat directly using friction of paddles in a water tank. This type of renewable energy device is a gamechanger, because it can generate and store heat with little losses in heat transportation. To make things more obvious than we already have at windheatingsystem.com we build a small paper mockup. To build a big one we need about 5.000 Euro. Contact F. Rincker +31644311561

The parts shown above are the wind turbine, axle, heat storage container and the padle fixed to tha axle. You can’t see the water in the heat storage container, that heats up as it gets stirred by the paddle.

A (lossless) simulation of how a similar device absorbs wind energy turning it into heat over time. In reality the temperature will drop when wind is low.

Vertical axis wind turbines (VAWTs) are slightly less efficient than horizontal axis turbines, but the cost of building them is less and the size can easily compensate. What is shown above could be build at a scale of 1:10 or 1:100, the idea would be the same. The underground heat storage container will accumulate heat as the paddle churns water until the water boils and evaporates. Anyone that needs heat can either use the water directly or use a heat exchanger to pipe the heat to their homes.

The power accumulated by the device is a function of the efficiency of the VAWT, windspeed, and of the ability of the paddle to churn the water. If the water starts to move with the paddles, the power conversion will be less, the turbine will speed up until it doesn’t absorb any windpower anymore (when it turns with the wind or loses as much as it gains). Ensuring energy absorbtion by the water however is not difficult.

 

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Vegaoarma? Lupine als vleesvervanger

Soms blijft een naam in je hoofd hangen omdat je hij nieuw is en geen betekenis heeft..Lupine had dat effect recent bij mij. Deze plant zou een prima grondstof zijn voor vleesvervangers aldus de Vegetarische Slager. Lupine blijk ik al te kennen als Vingerhoedskruid, de plant met giftige bloemen waarmee je zo makkelijke bijen en hommels kan vangen door ze dicht te knijpen als de hommel in de vingerhoed is gekropen. 

Kennelijk zitten er niet gifdige delen aan deze plant met eiwitten enz. De gebruikte variant ziet er anders uit, heeft kleinere bloempjes en veel meer groen. De vegetarische slager schrijft er over:

"Het is een robuuste plant, die gemakkelijk geteeld kan worden zonder gebruik te maken van kunstmest en chemische middelen." 

Een veld mooie lupines 

We kochten een portie Vegetarische Shoarma, dwz lupine verwerkt tot. Ontraditioneel maakten we die klaar met wat pasta en courgette..de vraag is of je nog groente moet eten bij een vegetarische maaltijd. Enfin, het resultaat hieronder..

Deze vegoarma werdt niet heel hardt aangebakken, dus of lupine een knapperig korstje ontwikkeld hebben we niet kunnen ontdekken. De consistentie is gelijkmatig, een beetje zwakker dan kipfilet, je bijt er (te) makkelijk doorheen. Er zijn geen vezels of taai vet e.d. dus de overeenkomst met shoarma is niet merkbaar. De smaak is echter goed. Je zou het wel door shoarma kunnen bijmengen, dat zal de meeste mensen ontgaan. Toch is het maken van vleesvervangers een beetje knullig. Mischien kan beter gewerkt worden aan in kleine kip, koe of varken geperste lupine brokjes, net als voorgebakken aardappels en ingevroren doperwten, want vlees vervangen doet het prima.

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Concentrated Photovoltaics in Action

Recently a new Amonix CPV (concentrated photovoltaics) plant came online in Colorado. CPV cuts cost over normal PV by using optics and special photovoltaic cells to get more power out of less raw materials. Silicon wafers are becoming cheaper through innovation every year, but they still cost more than a plastic lens that can concentrated the light from a bigger area on a smalled cell. CPV only makes sense if you also track the sun, this in itself can lead to up to 38% more output. 

CPV plant in Alamosa Colorado with $90 mln funding 

CPV has existed for decennia now, especially because the cell price was so high before. Lots of DOE funds have gone up in smoke developing systems that where not deployed. The list is quite long, and the investor capture stories easy to find, we reported on some here. The truth of CPV is that it is a lot cheaper than full silicon pv. That usually means it is kept off the market until it becomes as expensive as all the other products, so that entering the market ultimately fails.

Mirror based CPV Source

To break the market protective forces (usually the banks) subsidies are necessary. The free market is not free at all, it is divided, and the powerbase to control it is fossil feul credit. In that sense renewables are a real disruptive force, because if you have a 5 MW CPV plant, you can freely manufacture a lot without needing any credit to buy fossil fuels. 

Sp

Parabolic mirror based CPV by Cyrium, with $15 mln funding

There is several ways to do CPV. It boils down to how do you concentrate the light. Direct sunlight can be focussed by lenses and mirrors, in the case of a mirrors there are three options, in the case of lenses there are two. Mirrors can be parabolic, which causes them to concentrate all the light in one focal point or area, where the PV cell is placed. Very high concentrations can be reached, up to 10.000 sun, so the limiting factor is the thermal integrity of the cell.  

Fresnel mirror CPV system 

Fresnel mirror systems for CPV are rare, they are usually used for concentrated solar thermal applications, but also in combined systems using a parabolic trough mirror. The mirrors produce a line focus on which one can place PV cells. The nice thing is that one can keep te cells cool by running water behind them, which both produces steam or hot water and inproves the performance of the cells. 

PV cells in a linear focus CPV installation

A light guide CPV works by using lenses or mirrors to change the direction of light. Like with glass fibre, under certain circumstances light can be moved around even around corners with little loss. The most common way to do it is by funnel shaped mirrors. 

An experimental CPV device with a ball lens, but beneath it you can see light funnels 

When a lens is used the direction of light is changed by making it pass through material that slows it down. Because of the speed difference of light in air and glass for instance, the light changes direction at the edge of the glass. Lenses can be solid or fresnel. Solid lenses have a limited size because of the weight of the material. That is why fresnel lenses where invented, the earliest in light houses. The idea behind a fresnel lens is that as the light does not change direction as it passes through the bulk of the lens, you might as well leave that part out. So fresnel lenses are hollowed out and flattened spherical lensen.

Lighthouse Fresnel 

Fresnels can also be made from plastic, PET (same stuff as waterbottles) and be durable in the UV (that usually causes yellowing of plastic). Amonix uses them, and below you see another design. PET fresnel lenses are expensive as a consequence of their PV use, you pay 80,- Euro for a lens of about 33 x 33 cm. One could imagine someone collecting waterbottles to turn them into CPV fresnel lenses.

Fresnel lens CPV 

Another Fresnel lens CPV product 

Yet another type of CPV installation 

The cells used in CPV applications are usually multijunction cells. They consiste of stacked cells with different spectral sensitivity so more of the light spectrum can be converted to electricity. The cells also need to be able to widtstand high temperatures, a 1 x 1 meter fresnel lens will melt stone easily. The optimium is sought where the higher concentration of light leads to more output, while the increased resistance and lower efficiency due to higher temperatures. The cell size also determines the cost, so has to be minimal. 

Amonix multi junction cell wafer

Soitec Concentrix CPV

Solfocus CPV

Multi junction cells Solar Junction