A new type of solar cell, made from a material that is dramatically cheaper to obtain and use than silicon, could generate as much power as today’s commodity solar cells.Researchers developing the technology say that it could lead to solar panels that cost just 10 to 20 cents per watt. Solar panels now typically cost about 75 cents a watt, and the U.S. Department of Energy says 50 cents per watt will allow solar power to compete with fossil fuel.
In the past, solar researchers have been divided into two camps in their pursuit of cheaper solar power. Some have sought solar cells that can be made very cheaply but that have the downside of being relatively inefficient. Lately, more researchers have focused on developing very high efficiency cells, even if they require more expensive manufacturing techniques.
The new material may make it possible to get the best of both worlds—solar cells that are highly efficient but also cheap to make.
One of the world’s top solar researchers, Martin Green of the University of New South Wales, Australia, says the rapid progress has been surprising. Solar cells that use the material “can be made with very simple and potentially very cheap technology, and the efficiency is rising very dramatically,” he says.
Perovskites have been known for over a century, but no one thought to try them in solar cells until relatively recently. The particular material the researchers are using is very good at absorbing light. While conventional silicon solar panels use materials that are about 180 micrometers thick, the new solar cells use less than one micrometer of material to capture the same amount of sunlight. The pigment is a semiconductor that is also good at transporting the electric charge created when light hits it.
“The material is dirt cheap,” says Michael Grätzel, who is famous within the solar industry for inventing a type of solar cell that bears his name. His group has produced the most efficient perovskite solar cells so far—they convert 15 percent of the energy in sunlight into electricity, far more than other cheap-to-make solar cells. Based on its performance so far, and on its known light-conversion properties, researchers say its efficiency could easily rise as high as 20 to 25 percent, which is as good as the record efficiencies (typically achieved in labs) of the most common types of solar cells today. The efficiencies of mass-produced solar cells may be lower. But it makes sense to compare the lab efficiencies of the perovskite cells with the lab records for other materials. Grätzel says that perovskite in solar cells will likely prove to be a “forgiving” material that retains high efficiencies in mass production, since the manufacturing processes are simple.
Sunday, 11 August 2013
Thursday, 25 July 2013
Cleverly combining solar PV with solar thermal to reach 80% conversion efficiencyConcentrating the sun's ray onto solar photovoltaic (PV) modules requires walking the fine line between optimizing power output and not literally melting your very expensive super-high-efficiency solar cells. A team led by IBM Research seems to have found a way to push back the line. They have created a High Concentration PhotoVoltaic Thermal (HCPVT) system that is capable of concentrating the power of 2,000 suns onto hundreds of triple junction photovoltaic chips measuring a single square centimeter each (they even claim to be able to keep temperatures safe up to 5,000x). The trick is that each solar PV cell is cooled using technology developed for supercomputers; microchannels inspired by blood vessels but only a few tens of micrometers in width pipe liquid coolant in and extract heat "10 times more effective than with passive air cooling."
The beauty is that this heat is not just thrown away. This system gets useful work out of it. So while the PV modules are 30%+ efficient at converting the sun's light into electricity, another 50% of the sun's energy is captured as heat and can then be used to do things like thermal water desalination and adsorption cooling. This means that the system is capable of converting around 80% of the collected solar energy into useable energy (though the electricity is of course more useful than the thermal energy).
Wednesday, 24 July 2013
From stadiums in Brazil to a bank headquarters in Britain, architects led by Norman Foster are integrating solar cells into the skin of buildings, helping the market for the technology triple within two years. Sun-powered systems will top the stadia hosting 2014 FIFA World Cup football in Brazil. In Manchester, northern England, the Co-operative Group Ltd. office has cells from Solar Century Holdings Ltd. clad into its vertical surfaces.The projects mark an effort by designers to adopt building-integrated photovoltaics, or BIPV, where the power-generating features are planned from the start instead of tacked on as an afterthought. Foster and his customers are seeking to produce eye-catching works while meeting a European Union directive that new buildings should produce next to zero emissions after 2020.
“Building integrated solar in office buildings and factories which generate energy consistently during daylight hours, whilst not requiring additional expensive land space or unsightly installations, is seen as the most obvious energy solution,” said Gavin Rezos, principal of Viaticus Capital Ltd., an Australian corporate advisory company that’s one of the private equity funds putting money into the technology.
The market for solar laid onto buildings and into building materials is expected to grow to $7.5 billion by 2015 from about $2.1 billion, according to Accenture Plc, citing research from NanoMarkets. Sales of solar glass are expected to reach as much as $4.2 billion by 2015, with walls integrating solar cells at $830 million. About $1.5 billion is expected to be generated from solar tiles and shingles.
The technology provides a respite for solar manufacturers, opening the way for them to charge a premium for products. Traditional solar panel prices have fallen 90 percent since 2008 due to oversupply, cutting margins and pushing more than 30 companies including Q-Cells SE and a unit of Suntech Power Holdings Co. into bankruptcy.
Tuesday, 23 July 2013
The 392MW Ivanpah solar tower power station is the biggest concentrated solar thermal project in the world. It is also the most visually arresting. It features three huge towers, each 150m tall, surrounded by huge fields of mirrors that will focus the sun’s energy on a receiver located at the top of the tower. Water is boiled to create steam that then drives the turbines. It’s solar generation at a massive scale, made more impressive by its surroundings. Even though it spreads over so many hectares, its size pales against the grandeur of the stunning Mojave landscape.Ivanpah is not the only solar power station of large-scale being built in this art of the world. To the north, across the state border in Nevada, a 110MW solar tower with storage facility is being built by SolarReserve.
To the west, in the heart of California’s “high desert”, First Solar is nearing completion of a 250MW AVSR solar PV project near Lancaster, while down the road SunPower has begun construction of a 579MW solar PV plant of their own. A little further north, the tables are turned as SunPower puts the finishing touches to its 250MW CVSR project, while First Solar is about to trump it with the 550MW Topaz solar PV project, which is half way through construction.
But even as these massive projects are nearing completion, the question is being asked: Does the future of solar really lie in more of these large scale projects? Even the owners of these huge projects are not so sure.
NRG, the largest owner of generation assets in the US, and part owner of the Ivanpah project, says it is uncertain about the future of such large scale projects, because they are hugely capital-intensive. “These projects are massive, and even though the technology is proven it is very difficult to continually build these in the US, because there are limits to where these projects can be placed,” says Todd Michaels, the head of distributed generation for NRG. “Utilities are fully procured out in the south-west where this technology most appropriate. You are seeing a move to push new solar projects into distribution network. That’s where our CEO David Crane is saying these projects are heading – into distributed energy in general and solar in particular.”
CEO SunPower Tom Werner is building two of these massive projects, but even he says he is not sure where the future lies, which is why he is having his company hedge his bets. “We large scale utility, large and small distributed generation , and rooftop,” Werner told RenewEconomy is a recent interview. “We purposely straddle all three because we don’t know the answer to your question, to be honest. “Here’s how we look at it. The beauty of solar is that it is easy to site, where there is sun. It’s quick to install, scaleable, and you can make it big or small. Those are huge advantages. “So you can though utility problem on its head – you ask yourself, where do I have transmission, where do I have load, and then you can put put solar in it.
Monday, 22 July 2013
Two of the key metrics that will be watched closely in the global solar industry reporting season that has just commenced are the price of panels sold, and the cost of manufacture. The difference is what the industry calls the margin. ...REC Solar, one of the leading European solar companies produced these two graph in its results last week.
The first is the price of solar modules, which shows a rebound. The second is the crucial one for the future of the industry, and its ability to undercut fossil fuels over the long term, because it shows that the cost of manufacture of a solar module will fall around 20 per cent over the year – despite the 60-80 per cent falls achieved over the previous three to four years. The same story is expected to be repeated among many other manufacturers.
Sunday, 26 May 2013
As proponents of green energy go, Samuel Yang and Ben Waters could hardly be less alike. Samuel Yang, dubbed by the Chinese media the ''godfather of solar energy'', is a Buddhist vegan who befriended solar scientists while studying economics at Macquarie University in Sydney. He returned to China to found four of the largest solar photovoltaic companies in the world.Ben Waters, director of Australia's sustainable business strategy for General Electric, sings in church choirs and, as a Hobart schoolboy, brooked bullying by opposing the Franklin River dam. He arrived at the giant corporation after years maintaining F/A-18 fighter jets.
GE's Ben Waters believes the Coalition might not scrap carbon tax. Photo: James Alcock Both Yang and Waters, though, share similar visions for the future of energy: the shift from large-scale, fossil-fuel power plants has to happen if we are to limit global warming, and the pace of the transition will surprise even supporters.
Of the two, Yang is arguably more of a revolutionary. As chief executive of Shanghai-listed Hareon Solar Technology, Yang is in the midst of a battle for survival in an industry that has soared about 50 per cent annually since 2002. Two of Yang's start-ups, JA Solar and Suntech, are among Chinese companies flooding global markets with low-cost solar PV. Suntech is also fending off creditors. ''This overcapacity is normal for any new industrial technology,'' Yang says on a visit to Melbourne this week. ''Solar technology is always advancing fast … and some companies will drop out.''
PV prices in Australia are now below 90¢ per watt, down as much as two-thirds in a couple of years. About one in eight Australian homes now have solar panels, and Yang says penetration rates could rise to 80 per cent in coming years given Australia's high electricity prices, ''such wonderful sun'', and the likely arrival of even cheaper solar PV and later low-cost batteries.
Yang won't say how much further prices will fall but any pause in the decline is likely to be temporary. Even the threat of European tariffs for alleged dumping is dismissed. ''It's a silly childish game,'' Yang says. ''I believe it won't last long.'' Yang bets European leaders will be wary of sparking a trade war with the growing Chinese market and losing jobs linked to the spread of cheap Chinese products. Yang's focus, though, is to expand his company into energy production itself. ''We have to invest in solar farms,'' he says. ''We should become energy suppliers.''
US industrial conglomerate GE, about 125 years old and worth about $250 billion, has investments in many industries but becoming a big power generator is not yet a priority. A major equipment supplier to fossil fuel industries such as coal and coal seam gas, GE also rivals Denmark's Vestas as the world's biggest producer of wind turbines. ''We're energy agnostic,'' Waters says. ''We want to be involved in the energy sector of the future and we're transitioning our business accordingly into distributed power, into renewables, into smart grids and energy storage.''
The spread of tri-generation, with plants generating heat, cooling and power to local precincts, is among GE's target businesses. The company is in talks with Queensland universities for campus-wide energy supplies and for Springfield, southeast of Brisbane, which will see its population surge five-fold to 100,000 over the next two decades.
The shift to locally supplied energy, potentially much more efficient to operate and with lower carbon emissions, means less future demand for power from the National Electricity Market. Power consumption from the NEM has been in decline for four years, and the loss of demand from aluminium smelters and other manufacturers - including Ford factories in Victoria from 2016 - is likely to see that trend continue.
GE, CSIRO and some 40 key power industry players are thrashing out future scenarios for the electricity sector. The Future Grid Forum, which includes an assessment of how the network can accommodate a much higher share of renewables over the next decade, will release its report in October - after the federal election.
Waters directs GE's ecomagination division in Australia, and chairs Sustainable Business Australia - which puts him at odds with firms opposed to a carbon price. GE imposed internal controls on carbon since 2005 and cut its footprint by 30 per cent since.
Saturday, 25 May 2013
Australian scientists have found a way of hugely increasing the efficiency of solar panels while substantially reducing their cost. The University of NSW researchers have come up with improvements in photovoltaic panel design that had not been expected for another decade.The breakthrough involves using hydrogen atoms to counter defects in silicon cells used in solar panels. As a consequence, poor quality silicon can be made to perform like high quality wafers. The process makes cheap silicon "actually better than the best-quality material people are using at the moment", the head of the university's photovoltaics centre of excellence, Professor Stuart Wenham, said. Silicon wafers account for more than half the cost of making a solar cell. "By using lower-quality silicon, you can drastically reduce that cost," he said. "We've been able to figure out what the secret is that enables hydrogen to sometimes work the way people want it to, and sometimes doesn't."
At present, the best commercial solar cells convert between 17 per cent and 19 per cent of the sun's energy into electricity. UNSW's technique, patented this year, should produce efficiencies of between 21 per cent and 23 per cent. ...
The price of solar panels has fallen by about 65 per cent in two years, partly due to a huge rise in production in China. Australians have been taking advantage of lower prices, with the number of homes with solar panels exceeding 1 million. The phenomenal growth has caused some casualties in the industry as companies have taken on massive debt to expand supply, then struggled with falling prices in saturated markets. Notable among them is the recent debt default by Suntech Power, once the world's largest solar-panel maker, founded by former University of NSW researcher Shi Zhengrong.
Panel prices are predicted to fall much further. European producers predict they will be 60 per cent cheaper by 2020. "Based on the technological advances we're making, we think that's certainly achievable," Dr Wenham said.
Eight commercial firms have signed up to be a partner in developing the technology to an industrial scale, including Suntech, which continues to operate from its base in the eastern Chinese city of Wuxi and has a research unit in Sydney.
Monday, 11 March 2013
With a run of recent summers of below par temperatures, energy pundits have been eagerly awaiting a good summer heat wave to see just how our electricity system would stand up. The big question was what would happen when all those newly installed air conditioners finally got ramped up, once the the la Nina cycle broke and we got a good roasting? Would a return to hotter conditions finally break the trend of declining energy demand over the last four or five years?Well it looks like we got the summer that would answer these questions, and the answers are no doubt causing a fair bit of head scratching amongst the pundits.
Since the last hot summer in 2010, our electricity system has seen a lot of changes. For one thing, almost 2 gigawatts of distributed generation has been added in the form of domestic solar PV. To put that in context, 2GW represents a touch under 10 per cent of average summer demand, though of course solar PV only produces at near maximum levels for a few hours in the middle of a sunny summer day. However, when solar PV is producing it takes away from the demand for electricity that otherwise would be dispatched across the poles and wires via our National Electricity Market – or NEM.
So with this summer just past setting new records for extreme heat, it’s a good time to point the summer sun on the NEM and see how it is standing up.
With blistering summer heat, particularly across New South Wales and Queensland, there was an expectation we might see new records in peak demand. But despite the weather and the supposed new air-conditioning load, the NEM doesn’t seem to have been pushed very hard at all during this last summer.
Monday, 11 February 2013
A new analysis from research firm Bloomberg New Energy Finance has concluded that electricity from unsubsidised renewable energy is already cheaper than electricity from new-build coal and gas-fired power stations in Australia. The modeling from the BNEF team in Sydney found that new wind farms could supply electricity at a cost of $80/MWh –compared with $143/MWh for new build coal, and $116/MWh for new build gas-fired generation. These figures include the cost of carbon emissions, but BNEF said even without a carbon price, wind energy remained 14 per cent cheaper than new coal and 18 per cent cheaper than new gas.“The perception that fossil fuels are cheap and renewables are expensive is now out of date”, said Michael Liebreich, chief executive of Bloomberg New Energy Finance. “The fact that wind power is now cheaper than coal and gas in a country with some of the world’s best fossil fuel resources shows that clean energy is a game changer which promises to turn the economics of power systems on its head,” he said.
The Greens Party has unveiled an ambitious new document that outlines possible pathways to turn Western Australia – one of the most energy-intensive states in the world – into one where its stationary energy needs are powered 100 per cent by renewable energy sources in less than two decades.The Greens offer two principal scenarios to transform the coal and gas-dependent grid known as the South West Interconnected System (SWIS), which includes the capital Perth and the most populous regions. The first involves a heavier reliance on solar thermal and storage technologies currently deployed in Spain, the US and elsewhere, while the second relies more on currently cheaper technologies such as wind energy and solar PV. Both are supported by bio-mass and pumped hydro.
According to Scott Ludlam, the WA-based Senator whose office anchored the report with the help of specialist consultants, the plan seeks to make two important points – one that it is feasible, and two, it will not cost much more than business as usual (BAU).
Indeed, even using somewhat conservative technology cost forecasts for the various forms of solar, and to allow for a safety-first approach to capacity requirements, the study concludes that the levellised cost of electricity in the various renewable scenarios ranges from $208/MWh to $221/MWh by 2029. (We go into detail further down)
The levellised cost of electricity in the BAU case is not much cheaper – $203/MWh. While it has lower up front capital costs – $20 billion vs $60 billion, the balance of the BAU scenario bill will be paid in fuel costs, which for gas and diesel customers in WA is already proving expensive and forcing those on isolated and remote areas in particular to already consider solar alternatives. ...
The document was drawn together by Ludlam’s team, but the detailed technology scenarios were put together by an engineering team from Sustainable Energy Now, and drew on previous work by the likes of CSIRO and Beyond Zero Emissions.
Rooftop solar continues to have a dramatic impact on the energy market in South Australia – the Australian state with the highest penetration of rooftop solar.As these graphs provided by Melbourne Energy Institute’s Mike Sandiford illustrate, the proliferation of solar PV is not just having an impact on overall demand in the state, it is also shaving and reshaping the peak demand curves.
The impact of solar PV in South Australia was recognised by a special study by the Australian Energy Market Operator last August. As we reported then, South Australia had some 267MW of rooftop solar as at June 30, representing one in five households. AEMO said rooftop solar was accounting for 2.4 per cent of overall demand, and more than one-third of the PV systems were operating at the time of peak demand at any one time.
These graphs deliver a further illustration of their impact, as they illustrate what happened in the latest months of December and January, traditionally the period of hottest temperatures and highest demand. (If the graphs are not easy to read we suggest you click on them to see them better).
The ones immediately below show the average demand curves in South Australia over the last five years. The pink line shows 2012/13. As Sandiford points out, midday demand in SA this summer is down 15 per cent on where it was five years ago, even though night-time demand is up, confirming the impact of solar PV.
The stunning set of data, cost profiles and market analysis produced in the first few weeks of calendar 2013 have confirmed what many had long suspected – that the global energy markets are changing faster than anyone had thought possible.The implications for the incumbent energy industry – be they generators, network operators or retailers – couldn’t be more significant. The business models that supported the ageing infrastructure are broken, and if they can’t adapt to the new environment, they may soon be out of business. The idea of a rapid change to a largely renewable energy grid no longer seems aspirational, it could be inevitable.
Consider what we have learned this week:
- The price of wind energy (and in some isolated cases solar PV), is already cheaper than coal and gas in Australia. This gap is likely to widen considerably in the coming decade.
- By the time new baseload capacity is required in 10 years time, other technologies, including solar thermal with storage, and concentrated solar PV, will also be cheaper than coal and gas. Marine energy and geothermal could be close to parity.
- But not only do we have “grid parity” at the utility level, we also have socket parity, which means that homeowners and businesses can lower their cost of electricity by installing solar panels on their roof.
- the growing impact of large scale renewables, the self consumption market driven by rooftop solar and battery storage, and the impact of energy efficiency schemes, is reshaping the profile of the energy market and the dynamics of the industry. Sometimes in the most dramatic way. Coal and gas fired generators are getting priced out of the market.
As investment bank UBS noted last week, we are facing a “solar revolution” in the energy industry, and another is on the way with battery storage. As we suggested last year, the change is so profound that existing business models appear broken. According to Macquarie Bank, the German energy model is already “kaput”.
As we have seen in Australia, the increase in renewables is pushing down wholesale electricity prices, forcing the closure or mothballing of 3,000MW of fossil fuel capacity. In Germany, the closure rate is so rapid that the electricity authority has had to step in to slow them down.
The more retailers and network operators seek to recoup their investment in the face of lower demand, the more customers will be tempted to look after their own energy needs. Even halting all subsidies for rooftop solar will not stop it, said Macquarie. “The ever-increasing (grid) prices for domestic and commercial customers as well as rapid solar cost declines have brought on the advent of grid parity for German roofs. Thus, solar installations could continue at a torrid pace,” it notes. The same applies for Australia. ... Coal-fired power stations will not get built, for reputational and economic reasons, and gas – the much touted transition fuel – may also not get a look in. “Costs are just falling so quickly and the cost of fossil fuel are so much higher than public perception,” said Kobad Bhavnagri, head of clean energy research for BNEF in Australia. ”We could leapfrog gas as transition fuel.”
Bhavnagri said that by 2020 the “world could look quite different”. The market operator and system will be more experienced and adept at handling intermittency. “The case for gas is not as strong as people assumed a few years ago.”
The upshot of that analysis is that the plants we will be building in the 2020s will be – because they are the cheapest options – large scale solar with storage and other dispatchable renewables. The economic case for existing fossil fuel generators will be further undermined.
This explains why the fossil fuel industry in Germany, and in Australia, have been trying to halt the expanse of renewables. The primary policy goal of generators and fossil fuel industry for the past decade or more has been one of delay – to push back the build up of renewables long enough to extract maximum value from their existing assets, and even to create space so they can build more assets. The extractive industries have the same, simple plan.
All the major Australian utilities made clear in their submissions to the Climate Change Commission that allowing the renewable energy target to stand – and more wind farms and large scale solar PV to be built – would reduce the profits of their generators, quite dramatically. Yet diluting that target would allow them to build more gas-fired generation.
This is also why the utilities have also argued against the Clean Energy Finance Corporation, because it is designed to help usher in those technologies such as solar thermal and ocean energy that will be competitive in a decade’s time. But they can’t be competitive if none are built, and installation and manufacturing costs are reduced.
Many European markets are now at critical junctures with high penetration of wind and solar. This includes Germany, Italy, Denmark, Spain and Portugal. Australia, should it maintain its current renewable energy target, will follow soon enough. Germany, while reducing subsidies, is still increasing its renewables targets – 40 per cent by 2020 and 80 per cent by 2030.
Its biggest challenge is to figure out how to redefine the market rules so that it can provide enough economic incentive to prevent too many closures of fossil fuel plants, and to encourage existing gas to stay open rather than coal. It needs these gas plants to assist with the transition.
Thursday, 11 October 2012
It the solar industry ever harboured any illusions about the challenges it is facing in imposing itself on a sector that has been virtually unchallenged for more than half a century, then they were certainly shattered by a series of attacks on their industry from utilities and pricing regulators over the last few weeks.Giles has a follow up article noting that the gross proposal has been abandoned, for now - Utilities say no to gross tariffs, yes to battery storage.It is now clear – if it wasn’t before – that Australian energy utilities are moving decisively against the proliferation of solar PV in an attempt to protect their revenues and business models, as we predicted they would back in June. This is the claim of the solar industry, and they point to numerous examples of tariff changes, network impediments and the lobbying and influence over regulators.
Last week’s revelation that the Queensland pricing regulator was contemplating a tariff that could effectively kill the attraction of solar PV to households struggling under the weight of rising prices from the grid, was proof enough. The attempt by TRUenergy to bring a halt to the deployment of both wind and solar – citing the potential of both to cripple the conventional energy industry – is a further sign of the desperation of those utilities struggling to adapt.
There is no doubt that the debate over clean energy has moved beyond day to day concerns around climate change (even if it should not), and now that technologies such as solar can deliver electricity at equal or lower prices at the socket, the issue of technology cost is also nearly redundant. The battleground has moved to regulation, and policy decisions on the framing of tariffs and how to reflect the true value of producing and consuming energy. And it’s largely played out out of the public eye.
What is required is a new way of looking at the energy system. The hub-and-spoke model, like fixed-line telephony, is creaking under the strain of the so-called “self consumption” market and the ability of customers to produce their own energy.
And the regulation has gotten off to a bad start. The premium tariffs designed to give rooftop solar a kick-start and help reduce its “soft costs” – those for installing, pricing and maintaining the systems – were so badly managed in some key states (NSW, in particular), that utilities seeking to defend their territory and business models were able to gain the moral high ground and win favourable tariff structures under the lofty goal of protecting disadvantaged consumers.
Most tariffs in the country are now structured around a net tariff, which enables a household to use the electrons they produce to offset their consumption and rising retail prices from the main utilities. But any excess production is sold back at a peppercorn rate (under the guise of network and other costs) to the retailers, who then sell it to a nearby customer for between two and four times as much.
However, the utilities have been quietly pushing for an even more draconian measure to be introduced – a gross tariff, which will require households to sell all their output to the retailer and then buy it back at an inflated price.
In a nod to the emerging power of the “pro-sumer”, Australian energy network operators and retailers have rejected a suggestion to move to gross tariffs for rooftop solar, saying it risked turning customers against them. Some suggest tariffs that would encourage homeowners to invest in more battery storage.Operators of electricity networks in Queensland and the energy retailers have overwhelmingly rejected a proposal by the state’s competition authority to introduce gross tariffs for rooftop solar, saying they would be complex, expensive and unfair to owners of rooftop panels.
The Queensland Competition Authority raised some eyebrows, and a few hackles, last month when it raised the prospect of a gross tariff in an issues paper it prepared for deliberations around a “fair and reasonable” tariff for solar.
The solar industry immediately condemned the proposal, saying the idea of forcing customers to sell all their solar power to retailers and then buy it back at a much higher price was inequitable and would effectively mean the death of the industry, as it would remove the attraction of rooftop systems as a hedge against rising electricity costs. And it seems that the utilities, who were suspected by some, of quietly advocating the move, have recognized the risk of putting consumers offside if such a tariff was introduced.
Most of the submissions put to the QCA by network operators and retailers pointed to the potential complexity and cost of a gross tariff – particularly in having to change metering arrangements.
Interestingly, it was TRUenergy, under fire over its proposal to sharply reduce the development of utility scale wind and solar developments by curtailing the ambition of the renewable energy target, which said most clearly that gross FITs were unfair because they were not equitable to consumers.
It noted that households that invested in rooftop photovoltaic systems do so in the expectation that they will be able to consume less grid energy, and thereby gain a sense of control over their costs.
“Under the proposed changes, households would be required to ‘sell’ energy to the grid at the cost of energy, and then ‘purchase’ energy for their own use, at up to three times the price,” it noted in its submission. It said it would be confusing and “may create the perception that electricity retailers are benefiting at the consumer’s expense.”
Wednesday, 28 March 2012
What’s better than one pancake? A whole stack of pancakes! Using the same logic, a team of MIT researchers have stacked a bunch of photovoltaic solar cells together to produce up to 20 times the power output of conventional solar power installations. ...
Basically, photovoltaic cells themselves aren’t all that expensive — according to MIT, they’re only around 35% of the total cost of a solar power installation. The main issue with solar power (and its main cost) is its low energy density, and thus the sheer surface area required to generate a sizable amount of electricity. This is why you need to cover your whole roof with cells to power your light bulbs, and why solar power plants would have to occupy tens of square miles of desert to produce as much power as a nuclear power plant.
To combat this issue, MIT has built 3D stacks of photovoltaic cells. These have the same footprint of a conventional, flat solar power setup — but as you can see in the picture above, the total surface area is much, much larger. The team built a variety of 3D designs, including a cube, and in all cases they produced between two and 20 times as much power as a flat panel. The most interesting facet of this discovery, though, is that these 3D stacks produce lots of extra power whenever the sun is near the horizon, i.e. in the morning, evening, winter, or at latitudes far away from the equator. With conventional, flat cells, it’s hard to capture low-angle light, but with an accordion structure (as pictured) the relative angle would be closer to 45 degrees.
