Capacity of the sun a a virtually limitless source of energy

"I'd put my money on the sun and solar energy. What a source of power! I hope we don't have to wait until oil and coal run out before we tackle that."
~Thomas Edison (1847~1931)

Buildings as Power Stations: a new vision for the built environment

"Every day we get enough energy from the sun to power our planet for 27 years...yet nearly all of this goes to waste."
~Research project SPECIFIC by Swansea University

Solar light for the base of the pyramid

"Did you know that breathing kerosene fumes is the equivalent of smoking two packets of cigarettes a day and two-thirds of adult females with lung cancer in developing nations are non-smokers.Yet globally, an estimated 500 million households still rely on kerosene or other liquid fuels for lighting." By yours trully

Energy: A multifaceted divide

“ Access to electricity is fundamental to opportunity in this age. It’s the light that children study by, the energy that allows an idea to be transformed into a real business. It’s the lifeline for families to meet their most basic needs, and it’s the connection that’s needed to plug Africa into the grid of the global economy.”
US President Barack Obama

Sustainability development

"In a few decades, the RELATIONSHIP between the environment, resources and conflict may seem almost as obvious as the connection we see today between human rights, democracy and peace"
~Wangari Maathai (1940 - 2011)

Sunday, February 1, 2015

Solar cell technology ideas with future potential to revolutionise public perception of renewable energy

Most of the products I’ll be mentioning here might still be in the pilot phase or yet to be commercialised but nevertheless,  if commercialised  can genuinely revolutionise how solar energy is perceived both from technological and architectural design point of view. Hitherto, the research on photovoltaic has mostly been mainly focussed on the improvement of conversion efficiency and cost reduction there by, neglecting the visual aesthetic aspect of the Solar PV. This has made solar PV to be viewed as incredibly ugly by the architect rendering it not meeting the desired design consideration. However, recently, in order to address this problems,  there is the increase in research interest on the solar PV architecture. Some of the architectural criteria put forward by architects from several countries that has to be considered are:
  • Natural integration of solar panels into the building
  • Panels must fit in architecturally with the total building concept
  • Good total composition of colours and materials 
  • Panels must be in harmony with the lines and pattern of the design
  • They must fit in with the character of the building
  • The PV system must be finely integrated with the other construction technology
  • The PV system must stimulate innovative designs
To address this issues different technological ideas seen as game changing and with potential to overhaul the way solar PV is used have been proposed.I'll also mention new PV technologies like perovskite solar cells with high efficiency that are also promising and some inventive ideas like hydrogen generation from solar cell that could in future help make renewable energy the mainstream source of energy. Note hereby that the numbering doesn’t have any implication in their order of importance.
1.Solar roads
Already Solar bike lane has been developed in Netherlands. The 70 m stretch of solar powered roadways, which was open for the public in November 12th 2014, connect Amsterdam suburbs of Krommenie. This new solar road came at a cost of €3 million.This is first step in a project that the local government hopes will see the path being extended to 100 m by 2016. It is made of crystalline silicon solar cell, developed as a prefabricated slabs with 2.5 by 3.5 m of concrete modules and covered with a 1 cm thick translucent layer of tempered glass .The surface of the road has been treated with a special non-adhesive coating, and the road itself was built to sit at a slight tilt in an effort to keep dust and dirt from accumulating and obscuring the solar cells.The solar panels will however generate 30% less energy than those placed on the roofs since it can not be adjusted to the position of the sun.The electricity generated can find practical application in street lighting.
Image:SolarRoad
Even though this has become the first solar road in the world , the idea of using existing road infrastructure to harvest solar energy is gaining momentum across the globe. Two Engineers couple from Idaho have already developed a prototype for solar panel units for roads. They estimate that It will be 50% to 300% more expensive to be built than the regular roads. However it will come with some features that include heating elements to stay snow/ice free, LEDs road markings to replace painting road markings, and attached cable corridors to store and treat stormwater and provide a "home" for power and data cables. These solar road panels can be installed on roads, parking lots, driveways, sidewalks, bike paths, playgrounds etc. They will be able to pay for themselves primarily through the generation of electricity, which can power homes and businesses connected via driveways and parking lots. If all the roads in the US were converted to solar roadways, they claim that, US would generate three times as much energy as it currently uses and cut greenhouse gases by 75%. Well this has not yet been scientifically proven but it is a promising idea that could revolutionise solar industry. Below are the prototypes.
Solar road prototype
Solar Roadways co-founders Julie and Scott Brusaw holding a prototype glass

The idea has been made into a futuristic design on how they should be.Below are some of those design ideas proposed
Artist's rendition of a fast food restaurant with Solar Road Panels.
(Graphic artist: Katherine Simons)
FYI I really loove Taco bell and one with solar parking lot wow that will be my favourite!
Artist's rendition of a bike path(Graphic design by Katherine Simons)
Artist's rendition of interstate dusk (Graphic design by Sam Cornett )
Artist's rendition of Sandpoint, Idaho - Home of Solar Roadways (Graphic artist: Sam Cornett)
2. White solar panels made to blend into buildings
With the goal of making solar PV aesthetically invisible , CSEM, a swiss private, nonprofit technology company has developed the world first white solar modules designed to blend into building instead of sitting on the roof thereby giving architect more flexibility in using solar power system. Solar cells are preferred to be as black as possible to absorb all the visible light in the electromagnetic spectrum since nothing absorbs light like black coloured materials. However due to the solar cell material characteristic especially for silicon based solar cells which is the dominant technology in the market today, their colour is blue (Of course thin film ). This gives no flexibility in the colour to be used especially in construction of buildings where blue colour for the case of crystalline silicon solar cell might not fit with the exterior design. CSEM develop the white solar panel by putting a plastic layer that goes over the panel.The layer act as a scattering filter that reflects all visible light, yet lets in infrared rays, which allows the panel to generate electricity. According to CSEM this layer can work with any crystalline silicon cell and can be applied to any existing panel whether it’s flat or curved. The layer being white, keeps the solar panels at a lower temperature, making them more efficient, as well as reducing air conditioning costs. This technology can be applied not only in architecture, but also in consumer goods such as laptops, phones, and vehicles such as cars and buses, as the layer is adapted to cover a range of colours.
3.Building-Integrated Photovoltaics (BIPV)
The advent of the “third generation solar cell” open up new possibilities for solar PV application in BIPV. The flexible thin film can be used anywhere in the building giving architects flexibility. This will take care of the architectural environment and building tradition but at the same time generate energy. The advantages of the BIPV over non-integrated systems is that initial cost can easily be offset by reducing the amount of money spent on materials (for Solar panels and roofing) and corresponding labour. There are different types of BIPV. They include tractile interlocking roof systems, See through solar panels that could be applied in windows, spray solar cell. This will also be explained in details in my next posting.Below are examples of amazing designs that shows how the BIPV could blend into our buildings with little negative impact on the aesthetic beauty of the buildings
shil.Shahvia gizmag.com
Willis Tower in Chicago. Image: Har
Tractile Interlocking roof systems
4.Printable solar cell
This has been developed by Australian Victorian Organic Solar Cell Consortium (VICOSC). They developed away to print solar cell directly onto plastics. The technology consist of a type of solar ink which is designed to cpature light and turn it into electricity. They therefore can be embedded into windows, smartphones and laptops.Even though they are less efficient with as compared to conventionally used silicon solar cell with improvement in technology we will see them improve.
Printable solar cell promises a future with solar cells that are light weight, mechanically flexible and can have almost arbitrary colours. This makes them interesting in particular to building intergration or mobiledevices application. The company Sigmaaldrich already developed the ink that can bue used for teh printable solar application. In future we will expect to see solar cells that can be printed as easily and as cheaply as” printing a photo on your inkjet”
Oxford Photovoltaics, a spin-off from the University of Oxford, have also developed cocolourful glass from printing that can generate electricity from the sun. They achieved this by adding a layer of transparent solid-state solar cells at most three microns thick to a conventional glass. It can also be dyed almost any colour. This can just be printed in the already available glasses in thebuildings
Below is an example of printable organic solar cell by MatHero project and cordinated by Germany's Karlsruhe Institute of Technology (KIT)
Oxford Photovoltaic's colourful printed solar glass Image from
Renewable energy installer
(Source: Karlsruhe Institute of Technology)
5. Water splitting
We do agree that due to the intermittent nature of renewable energy such as solar and wind energy, they can not by themselves be utilitized to meet the global energy demand.However, if we were to achieve this then, there are of course some issues relating to these renewable energues that need to be addressed. One of those is how to provide a stable, constant energy flux. For the case of solar energy, energy harvested from the sun needs to be efficiently converted into chemical fuels that can be stored, transported and used upon demand. Since battery as not been as successful as we would want it to be, the other desirable approach is through photoelectrolysis of water using solar panels to store solar energy in teh simplest chemical bond H2.Efficiently splitting water “industrial photosynthesis”could become the ultimate technology that could solve both energy and environmental probles altogethe in the future since it can be developed from renewabele energy sources. The photoelectrolysis can be accomplished using photovoltaic modules connected directly to electrolyzers and catalytic electrodes. Solar energy to hydrogen conversion efficiency is still very low. Recently however, a record efficency of 12.3% using perovskite solar cell was achieved. For more on perovskite solar cell check below.So if conversion efficiency of solar energy to hydrogen is improved, this could replace the fossil fuel and it will bring us close to the hydrogen economy.

6.Perovskite solar cell.
Last but not least in my big thing in solar cell technology is non other than perovskite solar cell.They were first unveiled in 2009 and have garnered massive research interest. They are feared by many as the new  solar cell in town that could possibly give silicon solar cell a run for their money. At the same time they can are seen as structure that can  be made in tandem with silicon solar cell to further improve the efficiency.Researchers at Stanford already shown that they were able to improve the efficieny of 11.4% efficieng silicon soalr cell to 17% when 12.7% perovskite solar cell was put on top of the silicon solar cell. Below is the structure of perovskite. solar cell. It can be made very cheapily and efficiently therefore regarded as a material that could make solar power “dirt cheap”. A typical material used as the ABX3 is methylammonium lead iodide(CH3NH3PbI3). For the hole interface material PEDOT:PSS is used while for the electron interface material  such  ZnO and TIO2 etc are being used.
Generic Structure of Perovskite Solar Cell
Compared to other technology the efficiency rise in perovskite within a span of just a few years has been very dramatic. This has not been seen in other solar cell technology.Current it stands at 19% efficiency.
source
Perovskite-based cells can be processed at much lower temperatures than ordinary PV cells. Moreover, their chemistry doesn’t involve rare elements such as tellurium, indium, or gallium. They have direct band gap and therefore absorbs light much more efficiently than silicon which has an indirect band gap.
Shows hydrogen and oxygen being generated (photo:EPFL)
They can be developed by spin coating .There are of course some problems that need to be addressed for it to be commercialized. At present, perovskite solar cells have very poor stability and breakdown after a few waters. One of the reseach that makes it very promising is its application in water splitting device. Michale Gratzel and colleagues at the  Swiss Federal Institute of Technology in Lausanne unveil a water splitting device containing a state-of-the-art perovskite solar cell.The cell has an efficiency of 17.3% and an open-circuit voltage of over 1V, meaning that just two cells connected in series can provide sufficient voltage to split water. A voltage of over 1.7V is required for water splitting to take place. To achieve this with silicon which currently has a maximum open circuit voltage of 0.75V require 3 cells connected in series while 2 cells in perovskite can acheive it. It is application in water already achieved an efficiency of 12.3% and future improvement is foreseeable.
The design structure for the water splitting © Science/AAAS
So our switch from the depleting fossil fuel to solar energy complemented by hydrogen from water spliiting might be nigh. In that future most of tour vehicles will be fueled by hydrogen and electricity will also be provided by hydrogen all obtained from abundant enery from mother nature. But until then lest work hard to come up with new solutions.