Solar Cells Made Of Tin Are ‘Very Promising’ As A Low-Cost Alternative Energy Source


Perovskite tin solar cell
Tin halide perovskite solar cells developed by researchers at the University of Oxford. University of Oxford

Proponents of sustainable energy in pursuit of a low-cost solar cell found relief in a widely available and cheap material: tin.

Researchers in both the U.S. and the UK are experimenting with tin as an alternative to lead in the production of perovskite solar cells, which convert light energy directly into electricity. Perovskite is a mineral composed mainly of calcium titanate whose structure is ideal for solar conversion. Most perovskite solar cell development has relied on lead to absorb sunlight, but the new studies, both released this week, make the case for using tin because it’s a less toxic material than lead.

“Tin is an inexpensive, abundant material and its use in solar cells would drive costs down while alleviating the kind of geopolitical supply chain issues that bedevil other solar cell materials,” Tina Casey, who writes about sustainability and new materials, notes in Clean Technica.

Solar panels are quickly becoming a global product. While the cost of solar panels varies widely, depending on their type and efficiency, overall, they’re becoming more affordable. According to Cost of Solar, solar panels are about half the price they were in 2000 and 100 times the price they were in 1977.

Today, solar costs about $0.70 to$0.73 per watt, although factoring in the “soft costs” of solar – things like installation and obtaining permits – can drive the prices up to about $4.72 per watt.

One of the studies focused on using tin in solar cells to drive down cost is from researchers at Northwestern University in Illinois. Their design for a new solar cell consists of five layers. The first two layers are of conducting glass and a layer of titanium dioxide. Then there’s the sheet of tin, followed by a coat of the electrical circuit. Finally, there’s a gold cap, which forms the back contact electrode of the cell.

“This is a breakthrough in taking the lead out of a very promising type of solar cell,” Mercouri G. Kanatzidis, an inorganic chemist whose expertise is in tin, said in a statement. “Tin is a very viable material, and we have shown the material does work as an efficient solar cell.”

Scientists in the UK have done similar experiments with using tin in perovskite solar cells and also report success with the material.
“The demonstration of solar cells using tin-based perovskites is a clear indication that good solar cell operation is not unique to lead, and therefore also opens up the use of other similar metals in the perovskite structure, leading to a multitude of new research avenues for optimising these materials,” Henry Snaith, the lead author of a study published in the journal Energy & Environmental Science, said in a statement.

The one downside to using tin in lieu of lead in solar cells is less efficiency. The UK team reported that their prototype demonstrated about 6 percent efficiency at turning sunlight into electricity – the U.S. team’s design achieved about the same – but researchers believe with more development that the solar cells can reach an efficiency closer to 20 percent.

Leading solar cell technology has roughly 25 percent conversion efficiency, according to Gizmag.


DOE considers entry of more solar plants

The Department of Energy (DOE) is looking to expand the solar power allocation under the Feed-in-Tariff scheme to 500 megawatts from the current 50 megawatts.

Energy Secretary Carlos Jericho Petilla said in a briefing Monday that ensuring adequate power during summer, when demand is at its highest, is a challenge. Petilla said while there were new plants supposed to be under development, such as the $600-million, 414-MW San Gabriel combined cycle natural gas-fired power plant in Sta. Rita, Batangas City, “I cannot leave that to chance.”

Hence, the DOE is considering allowing more solar power development with guaranteed power rates to boost supply during summer, when electricity reserves are often tight, Petilla said.

“The profile of solar really fits summer. We have the highest [production] in summer and in terms of pricing it actually works,” Petilla said, adding he hoped the allocation can be amended within the year following certification from the National Renewable Energy Board (NREB) that the current allocation of 50 MW is not enough.

The Energy Regulatory Commission (ERC) needs to approve the proposed additional allocation and it has asked for NREB’s endorsement.

As for the price impact, Petilla said NREB had conducted a study and found that the pass-on impact for an additional 450-MW under FIT is just up to P0.04 per kWh. “It can be zero. It can be negative, even, during summer,” Petilla said, referring to the high solar power production and very expensive power spot market costs during the summer season.

The DOE’s FIT allocation for solar power is only 50 MW but so far 80 MW of capacity have been committed by various players.

“It’s a race on whoever finishes registered projects first,” DOE director for renewable energy Mario C. Marasigan said. He was referring to the oversubscription in solar energy projects under FIT, which guarantees rates to be paid to developer-generators, and the DOE’s first-come, first-served policy on FIT allocation.

Read more:

World’s Largest Solar Plant Could Power 230,000 Homes

NRG Energy and MidAmerican Solar unveiled the new king in solar photovoltaic (PV) facilities this week.

Located on 2,400 acres of land between Yuma and Phoenix, AZ, Agua Caliente is now operational as the world’s largest PV solar facility in the world. The 290-megawatt (MW) project uses solar energy to avoid the annual emission of about 324,000 tons of carbon dioxide into the atmosphere—equivalent to taking nearly 70,000 cars off the road.

Under a 25-year power purchase agreement, NRG and MidAmerican sell solar power to Pacific Gas & Electric Co. At peak capacity, the plant will generate enough energy to power 230,000 homes.

NRG Energy and MidAmerican Solar announced the completion of Agua Caliente, the world's largest photovoltaic solar facility at 290 megawatts. The Arizona plant sells clean power to Pacific Gas & Electric Company under a 25-year power purchase agreement. Photo credit: Business Wire/NRG Energy
NRG Energy and MidAmerican Solar announced the completion of Agua Caliente, the world’s largest photovoltaic solar facility at 290 megawatts. The Arizona plant sells clean power to Pacific Gas & Electric Company under a 25-year power purchase agreement. Photo credit: Business Wire/NRG Energy

NRG was also involved in another record-setting solar project this year—the launch of Ivanpah, the world’s largest concentrating solar thermal power plant.

“Proving that we can build both the world’s largest solar thermal and now one of the world’s largest solar photovoltaic facilities advance NRG’s mission to reshape the energy landscape that is incredibly beneficial to both the economy and in how we produce and consume energy,” Tom Doyle, president of NRG Solar, said in a statement.

FirstSolar designed and constructed the project using advanced thin-film PV modules and will operate and maintain the facility for NRG and MidAmerican Solar. Peter W. Davidson, executive director of the Loan Programs Office (LPO) said the energy companies received a $967 million loan guarantee for Agua Caliente. In a blog post for the U.S. Department of Energy, Davidson displayed pride in aiding clean energy.

“Despite the strong and consistent public demand for greater development of solar energy, these achievements seemed more aspirational than attainable in 2009 , given the state of financial markets at the time,” Davidson wrote. “However, with the help of loan guarantees, these projects were able to move forward.

“We aren’t done yet. By the end of next year, we expect all five solar PV plants in our portfolio to be completed with a combined capacity of 1,510 MW—enough to power more than a quarter million average American homes.”

Agua Caliente, located in Yuma County, AZ, is now the largest solar photovoltaic power plant in the world. Photo credit: NRG Energy
Agua Caliente, located in Yuma County, AZ, is now the largest solar photovoltaic power plant in the world. Photo credit: NRG Energy

Agua Caliente is the largest of 10 operational utility-scale solar PV facilities in three states that NRG has an ownership interest in. By this time next year, it may no longer be the largest PV plant, as work continues on another MidAmerican project, the 550 MW Topaz Solar Farm in San Luis Obispo County, CA.

“In 2012, our company made a commitment to invest in its first utility-scale solar project to foster economic development while demonstrating our commitment to the environment,” said Richard Weech, chief financial officer of MidAmerican Renewables.

“It is exciting to see this project become fully operational and begin to realize the full benefit of emissions savings with the clean energy generated at Agua Caliente.”

Hope for shorter brownouts in Davao by Sunday fizzles out

DAVAO CITY – Just as when everyone was counting on finding some relief in an additional 105 megawatts of power to shorten the city’s four-to-six-hour brownouts, Steag’s State Power Inc. announced it could not get one of its rehabilitated units back on stream as initially scheduled on Sunday.

“While the repairs and restoration works of Unit 2 is substantially completed, the company needs more time to ensure that the unit is in excellent condition prior to commissioning and synchronization to the Mindanao grid,” SPI power plant manager Dr. Carsten Evers said in a statement.

Art Milan, executive vice president and corporate operating officer of the Davao Light and Power Company (DLPC), told a forum here on Friday the company was looking forward to the reinstatement of the unit as it would provide additional 105 MW to the Mindanao grid. Milan said this would result in shorter brownouts.

“Possibly, if one of the Steag’s units will finally run on Sunday, we might no longer experience brownouts during off peak hours,” said Milan, who spoke at a forum attended by barangay (village) captains, military officers and Mayor Rodrigo Duterte.

He said the city was experiencing a supply shortfall of 113 MW of power, or at least one-third of the 330 MW daily demand. The shortfall, he said, caused the rotating four-to-six-hour brownouts.

DLPC is owned by the Aboitiz group, which operates power generating plants.

This fact raised questions among consumers as other power utilities, which do not have generating capabilities, were brownout-free.

Evers said SPI might finally recommission the comnpany’s Unit 2 on or before May 8 while the target date for restoring Unit 1 is on June 1.

“We apologize for this delay and rest assured that we are doing everything we can to bring the units back to the grid,” Evers said.

The two identical power generation sets of the Mindanao coal-fired power facility, each having some 105 MW capacity, have been undergoing repairs after sustaining damage to their turbine-electric generating sets during the February 24 Mindanao-wide blackout.


Google, SunPower announce joint renewable energy financing deal

According to the agreement, Google will commit up to $100 million, with SunPower committing approximately $150 million. Thousands of homeowners are expected to finance solar power systems through SunPower solar leases as a result of this program, joining approximately 20,000 Americans already leasing from SunPower.

“We’re pleased to team with SunPower to make solar power accessible to more homeowners and offer families a more effective way to reduce their carbon footprint,” said Kojo Ako-Asare, head of corporate finance at Google. “Google is committed to promoting the efficient use of resources and expanding the use of renewable energy. Our partnership with SunPower makes good business sense and supports our goals for a clean energy future.”

Chuck Boynton, SunPower chief financial officer, agreed, adding that the funding will help make solar accessible to more families and allow those families to take control of their energy costs. “With the increased and growing interest in reliable, cost-effective solar from businesses and homeowners alike, Google’s leadership is helping take solar mainstream,” he said.

This agreement represents Google’s 16th renewable energy investment and its third residential rooftop solar investment. Overall, Google has invested more than $1 billion in renewable energy projects on three continents and across a range of technologies. Together, these projects can generate more than 2GW — enough electricity each year to power approximately 500,000 U.S. homes.


Going Off Grid Nears Tipping Point, Morgan Stanley Reports

Investment bank Morgan Stanley says it has been overwhelmed by the response to its recent analysis which suggested that the falling costs of both solar modules and battery storage presented a potential tipping point that would encourage huge numbers of homeowners and businesses in the US to go off grid.

The initial report, published earlier this month, has been followed up by a note from Morgan Stanley highlighting the extent to which investors had been unaware of these mega trends, which threaten massive disruption in the trillion-dollar utility business.

Sure, they had heard that solar was proving popular, but had no idea of the size of the market that Morgan Stanley had identified. And while most had been sceptical of the potential impact of battery storage, they were intrigued by the potential cost falls that could be achieved by Tesla, the electric car company, and its ability to monitor power levels in batteries and schedule a battery swap in the case of depletion.

More importantly, the investors were particularly focused on how utilities might respond. Solar, they suggested, should be seen as an opportunity and utilities should look at ways of becoming enablers of these technologies, rather than barriers.

Addressable distributed solar market in US could be 415GW

But first, back to the original report. There were a couple of major takeaways in this: One, the addressable solar market in the US is way bigger than anyone had previously imagined; and two, the Tesla gigawatt battery manufacturing facility could bring down the cost of storage quicker than anyone had imagined.

Even without the continuation of the 30 per cent investment tax credit – and taking into account the fact that many homes are unsuitable for solar – Morgan Stanley says its “base case” addressable market for distributed solar in the US is 240GW within five years.


Read more:

The disruptive potential of solar power

As costs fall, the importance of solar power to senior executives is rising.

The economics of solar power are improving. It is a far more cost-competitive power source today than it was in the mid-2000s, when installations and manufacturing were taking off, subsidies were generous, and investors were piling in. Consumption continued rising even as the MAC Global Solar Energy Index fell by 50 percent between 2011 and the end of 2013, a period when dozens of solar companies went bankrupt, shut down, or changed hands at fire-sale prices.

The bottom line: the financial crisis, cheap natural gas, subsidy cuts by cash-strapped governments, and a flood of imports from Chinese solar-panel manufacturers have profoundly challenged the industry’s short-term performance. But they haven’t undermined its potential; indeed, global installations have continued to rise—by over 50 percent a year, on average, since 2006. The industry is poised to assume a bigger role in global energy markets; as it evolves, its impact on businesses and consumers will be significant and widespread. Utilities will probably be the first, but far from the only, major sector to feel solar’s disruptive potential.

Economic fundamentals

Sharply declining costs are the key to this potential. The price US residential consumers pay to install rooftop solar PV (photovoltaic) systems has plummeted from nearly $7 per watt peak of best-in-class system capacity in 2008 to $4 or less in 2013.1 Most of this decline has been the result of steep reductions in upstream (or “hard”) costs, chiefly equipment. Module costs, for example, fell by nearly 30 percent a year between 2008 and 2013, while cumulative installations soared from 1.7 gigawatts in 2009 to an estimated 11 gigawatts by the end of 2013, according to GTM Research.

While module costs should continue to fall, even bigger opportunities lurk in the downstream (or “soft”) costs associated with installation and service. Financing, customer acquisition, regulatory incentives, and approvals collectively represent about half the expense of installing residential systems in the United States. Our research suggests that as they become cheaper, the overall costs to consumers are poised to fall to $2.30 by 2015 and to $1.60 by 2020.

These cost reductions will put solar within striking distance, in economic terms, of new construction for traditional power-generation technologies, such as coal, natural gas, and nuclear energy. That’s true not just for residential and commercial segments, where it is already cost competitive in many (though not all) geographies, but also, eventually, for industrial and wholesale markets. Exhibit 1 highlights the progress solar already has made toward “grid parity” in the residential segment and the remaining market opportunities as it comes further down the curve. China is investing serious money in renewables. Japan’s government is seeking to replace a significant portion of its nuclear capacity with solar in the wake of the Fukushima nuclear accident. And in the United States and Europe, solar adoption rates have more than quadrupled since 2009.

Exhibit 1

A sharp decline in installation costs for solar photovoltaic systems has boosted the competitiveness of solar power.

While these economic powerhouses represent the biggest prizes, they aren’t the only stories. Sun-drenched Saudi Arabia, for example, now considers solar sufficiently attractive to install substantial capacity by 2032,2 with an eye toward creating local jobs. And in Africa and India, where electric grids are patchy and unreliable, distributed generation is increasingly replacing diesel and electrifying areas previously without power. Economic fundamentals (and in some cases, such as Saudi Arabia, the desire to create local jobs) are creating a brighter future for solar.

Business consumption and investment

Solar’s changing economics are already influencing business consumption and investment. In consumption, a number of companies with large physical footprints and high power costs are installing commercial-scale rooftop solar systems, often at less than the current price of buying power from a utility. For example, Wal-Mart Stores has stated that it will switch to 100 percent renewable power by 2020, up from around 20 percent today. Mining and defense companies are looking to solar in remote and demanding environments. In the hospitality sector, Starwood Hotels and Resorts has partnered with NRG Solar to begin installing solar at its hotels. Verizon is spending $100 million on solar and fuel-cell technology to power its facilities and cell-network infrastructure. Why are companies doing such things? To diversify their energy supply, save money, and appeal to consumers. These steps are preliminary, but if they work, solar initiatives could scale up fast.

As for investment, solar’s long-term contracts and relative insulation from fuel-price fluctuations are proving increasingly attractive. The cost of capital also is falling. Institutional investors, insurance companies, and major banks are becoming more comfortable with the risks (such as weather uncertainty and the reliability of components) associated with long-term ownership of solar assets. Accordingly, investors are more and more willing to underwrite long-term debt positions for solar, often at costs of capital lower than those of traditional project finance.

Major players also are creating advanced financial products to meet solar’s investment profile. The best example of this to date is NRG Yield, and we expect other companies to unveil similar securities that pool renewable operating assets into packages for investors. Google has been an active tax-equity investor in renewable projects, deploying more than $1 billion since 2010. It also will be interesting to track the emergence of solar projects financed online via crowdsourcing (the best example is Solar Mosaic, which brings investors and solar-energy projects together). This approach could widen the pool of investors while reducing the cost of capital for smaller installations, in particular.

Disruptive potential

The utility sector represents a fascinating example of the potential for significant disruption as costs fall, even as solar’s scale remains relatively small. Although solar accounts for only less than half a percent of US electricity generation, the business model for utilities depends not so much on the current generation base as on installations of new capacity. Solar could seriously threaten the latter because its growth undermines the utilities’ ability to count on capturing all new demand, which historically has fueled a large share of annual revenue growth. (Price increases have accounted for the rest.)

Depending on the market, new solar installations could now account for up to half of new consumption (in the first ten months of 2013, more than 20 percent of new US installed capacity was solar). By altering the demand side of the equation, solar directly affects the amount of new capital that utilities can deploy at their predetermined return on equity. In effect, though solar will continue to generate a small share of the overall US energy supply, it could well have an outsize effect on the economics of utilities—and therefore on the industry’s structure and future (Exhibit 2).

Exhibit 2

Although solar power will continue to account for a small share of the overall US energy supply, it could well have an outsize effect on the economics of utilities.

That’s already happening in Europe. Over the last several years, the demand for power has fallen while the supply of renewables (including solar) has risen, driven down power prices, and depressed the penetration of conventional power sources. US utilities can learn many lessons from their European counterparts, which for the most part stood by while smaller, more nimble players led the way. Each US utility will have to manage the risks of solar differently. All of them, however, will have to do something.

Broader management implications

As solar becomes more economic, it will create new battlegrounds for business and new opportunities for consumers. When a solar panel goes up on a homeowner’s roof, the installer instantly develops a potentially sticky relationship with that customer. Since the solar installation often puts money in the homeowner’s pocket from day one, it is a relationship that can generate goodwill. But, most important, since solar panels are long-lived assets, often with power-purchase agreements lasting 15 or 20 years, the relationship also should be enduring.

That combination may make solar installers natural focal points for the provision of many products and services, from security systems to mortgages to data storage, thermostats, smoke detectors, energy-information services, and other in-home products. As a result, companies in a wide range of industries may benefit from innovative partnerships built on the deep customer relationships that solar players are likely to own. Tesla Motors already has a relationship with SolarCity, for example, to develop battery storage coupled with solar. It is easy to imagine future relationships between many other complementary players. These possibilities suggest a broader point: the solar story is no longer just about technology and regulation. Rather, business-model innovation and strong management practices will play an increasingly important role in the sector’s evolution and in the way it engages with a range of players from other industries. Segmenting customers, refining pricing strategies, driving down costs, and optimizing channel relationships all will figure prominently in the solar-energy ecosystem, as they do elsewhere.

As solar becomes integrated with energy-efficiency solutions, data analytics, and other technologies (such as storage), it will become an increasingly important element in the next generation of resource-related services and of the world’s coming resource revolution. In the not too distant future, a growing number of industries will have to take note of the promise, and sometimes the threat, of solar to business models based on traditional energy economics. But, in the meantime, the battle for the customer is taking place today, with long-term ramifications for existing industry structures.

Obama launches measures to support solar energy in US

President Barack Obama AP FILE PHOTO


WASHINGTON — The White House Thursday announced a series of measures aimed at increasing solar energy production in the United States, particularly by encouraging the installation of solar panels in public spaces.

President Barack Obama and his Democratic allies in Congress want laws to fight climate change and reduce greenhouse gas emissions, but Republicans, who hold the majority in the House of Representatives, have blocked all legislative efforts since 2011.

In response, the president has switched tactics, using his regulatory and administrative powers to enact his climate change policies.

Thursday, the White House launched a program to encourage federal agencies, military installations, and publicly-subsidized buildings in the Washington area to install more solar panels on roofs, covered parking garages and open land.

And, earlier in the week, the Energy Department guaranteed at least $2.5 billion in loans for “innovative” solar projects.

The Environmental Protection Agency also pledged Thursday to double the use of renewable energy at its network of 1,500 partners organizations — including schools, public buildings, and businesses — within the next 10 years.

Another $15 million will be dedicated to local initiatives to boost solar capacity.

According to the White House, the United States today can generate up to 13 gigawatts of energy from solar power, or enough to power 2.2 million homes, up from just 1.2 gigawatts in 2008.

The federal government is working on granting permits which by 2020 would generate enough power to support six million households, it added.

The average cost of solar panels has dropped more than 60 percent since the beginning of 2010, the White House said.

The president also has significant leverage to influence on carbon emission levels through limiting the federal government’s energy consumption, especially within the Defense Department, which is the biggest energy consumer in the country.

Read more:

The Solar Industry Has Been Waiting 60 Years For This To Happen — And It Finally Just Did

It’s now a question of how and where, not if, solar becomes a dominant force in energy markets.

AllianceBernstein’s Michael Parker and Flora Chang published a note last week with the following chart showing how rapidly the cost of solar on a real-dollars-per-million-BTU equivalent basis has, in many instances, come to match that of conventional fuels.

Nothing else looks like this. And the title of the chart, Welcome to the Terrordome, reflects this almost violent decline in solar pricing.


solar terrordomeAllianceBernstein


The authors write:

Exhibit 2 is the chart the solar industry has been working towards for 60 years. Solar is now – in the right conditions – cheaper than oil and Asian LNG on an MMBTU basis. Yes, we are using utility- scale solar costs in developing markets with lots of sun. But that describes the growth markets for global energy today. For these markets solar is just cheap, clean, convenient, reliable energy. And since it is a technology, it will get even cheaper over time. Fossil fuel extraction costs will keep rising. There is a massive global market for cheap energy and that market is oblivious to policy changes at the NDRC, MITI, the EU or the CPUC.

Solar still makes up only a tiny fraction of overall energy usage on an absolute basis — about 0.17%. But it’s an unstoppable trend.

For now, this minuscule starting point is great for investors, Parker and Chang say, because it will continue to be more attractive than oil and gas prices, which are set to keep climbing. Bernstein’s notoriously bullish energy team forecasts an oil price of $150 by 2020. Parker also explains that if utilities try to respond, growth in the storage market will accelerate.

As solar costs fall, the price that end markets will pay for solar energy is set by oil and remains unchanged. The solar industry (upstream and downstream) collects all of the value created by improvements in the technology. The behavior from here seems clear: the solar industry will expand. Retaliatory steps from distribution utilities will increase the market for cost-effective battery storage. This becomes – initially – a secondary market for battery technologies being developed for the auto sector. A failed battery technology in the auto sector (too hot, too heavy, too rigid a form factor) might well be perfect for the home energy storage market…. with an addressable end market of 2 billion backyards.

But there’s another, Terrordome-esque scenario Parker outlines, which he calls global energy deflation. It would be great news for consumers, but investors would get killed. He uses the crude forward curve as a reference point:


bernstein oilAllianceBernstein


He writes:

…the risk is that I am being too conservative. It may be that oil and gas producers sitting on large reserves will not wait for deflating energy prices a decade from now before changing behavior. Rather, the expectation of energy deflation may be enough. If the downward sloping forward curve is ever accepted as permanent, rational behavior from energy producers will guarantee it is so. Sitting on oil and gas reserves for the benefit of generations yet to come ceases to be a rational strategy if that reserve represents a depreciating rather than an appreciating asset. This is the hidden flaw with the “equal and opposite/ too small to matter” formulation. Ultimately what may kill the solar sector – and every other part of the energy market – for equity investors is not renewable technology and battery storage turning into behemoths, but the realization of that future as inevitable. 

Actually, solar utilities seem to have been around for longer than 60 years. We dug through the Library of Congress’ image archives to find a solar water heater dated 1929 (PDF):


old solar panel

Read more:

I’m Now Convinced That Global Solar Dominance Is In Sight

Solar power will slowly squeeze the revenues of petro-rentier regimes in Russia, Venezuela and Saudi Arabia. They will have to find a new business model, or fade into decline


Solar power has won the global argument. Photovoltaic energy is already so cheap that it competes with oil, diesel and liquefied natural gas in much of Asia without subsidies.

Roughly 29pc of electricity capacity added in America last year came from solar, rising to 100pc even in Massachusetts and Vermont. “More solar has been installed in the US in the past 18 months than in 30 years,” says the US Solar Energy Industries Association (SEIA). California’s subsidy pot is drying up but new solar has hardly missed a beat.

The technology is improving so fast – helped by the US military – that it has achieved a virtuous circle. Michael Parker and Flora Chang, at Sanford Bernstein, say we entering a new order of “global energy deflation” that must ineluctably erode the viability of oil, gas and the fossil fuel nexus over time. In the 1980s solar development was stopped in its tracks by the slump in oil prices. By now it has surely crossed the threshold irreversibly.

The ratchet effect of energy deflation may be imperceptible at first since solar makes up just 0.17pc of the world’s $5 trillion energy market, or 3pc of its electricity. The trend does not preclude cyclical oil booms along the way. Nor does it obviate the need for shale fracking as a stop-gap, for national security reasons or in Britain’s case to curb a shocking current account deficit of 5.4pc of GDP.

But the technology momentum goes only one way. “Eventually solar will become so large that there will be consequences everywhere,” they said. This remarkable overthrow of everything we take for granted in world energy politics may occur within “the better part of a decade”.



If the hypothesis is broadly correct, solar will slowly squeeze the revenues of petro-rentier regimes in Russia, Venezuela and Saudi Arabia, among others. Many already need oil prices near $100 a barrel to cover their welfare budgets and military spending. They will have to find a new business model, or fade into decline.

The Saudis are themselves betting on solar, investing more than $100bn in 41 gigawatts (GW) of capacity, enough to cover 30pc of their power needs by 2030 rather than burning fossil fuel needed for exports. Most of the Gulf states have comparable plans. That will mean more crude – ceteris paribus – washing into a deflating global energy market.

Clean Energy Trends says new solar installations overtook wind turbines worldwide last year with an extra 36.5GW. China alone accounted for a third. Wind is still ahead with 2.5 times old capacity but the “solar sorpasso” will be reached in 2021 as photovoltaic (PV) costs keep falling.

The US National Renewable Energy Laboratory says scientists can now capture 31.1pc of the sun’s energy with a 111-V Solar Cell, a world record but soon to be beaten again no doubt. This will find its way briskly into routine use. Wind cannot keep pace. It is static by comparison, a regional niche at best.

A McKinsey study said the average cost of installed solar power in the US across all sectors has dropped to $2.59 from more than $6 a watt in 2010. It expects this fall to $2.30 by next year and $1.60 by 2020. This will put solar within “striking distance” of coal and gas, it said.

Solar cell prices have already collapsed so far that other “soft costs” now make up 64pc of residential solar installation in the US. Germany has shown that this too can be slashed, partly by sheer scale.

It is hard to keep up with the cascade of research papers emerging from brain-trusts in North America, Europe and Japan, so many brimming with optimism. The University of Buffalo has developed a nanoscale microchip able to capture a “rainbow” of wavelengths and absorb far more light. A team at Oxford is pioneering use of perovskite, an abundant material that is cheaper than silicon and produces 40pc more voltage.

One by one, the seemingly intractable obstacles are being conquered. Israel’s Ecoppia has just begun using robots to clean the panels of its Ketura Sun park in the Negev desert without the use of water, until now a big constraint. It is beautifully simple. Soft microfibers sweep away 99pc of the dust each night with the help of airflows.

Professor Michael Aziz, at Harvard University, is developing a flow-battery with funding from the US Advanced Research Projects Agency over the next three years that promises to cut the cost of energy storage by two-thirds below the latest vanadium batteries used in Japan.

He said the technology gives us a “fighting chance” to overcome the curse of intermittency from wind and solar power, which both spike and drop off in bursts. “I foresee a future where we can vastly cut down on fossil fuel use.”

Even thermal solar is coming of age, driven for now by use of molten salts to store heat and release power hours later. California opened the world’s biggest solar thermal park in February in the Mojave desert – the Ivanpah project, co-owned by Google and BrightSource Energy – able to produce power for almost 100,000 homes by reflecting sunlight from 170,000 mirrors onto boilers that generate electricity from steam. Ivanpah still relies on subsidies but a new SunPower project in Chile will go naked, selling 70 megawatts into the spot market.

Deutsche Bank say there are already 19 regional markets around the world that have achieved “grid parity”, meaning that PV solar panels can match or undercut local electricity prices without subsidy: California, Chile, Australia, Turkey, Israel, Germany, Japan, Italy, Spain and Greece, for residential power, as well as Mexico and China for industrial power.

This will spread as battery storage costs – often a spin-off from electric car ventures – keep dropping. Sanford Bernstein says it may not be long before home energy storage is cheap enough to lure households away from the grid en masse across the world.

Utilities that fail to adapt fast will face “disaster”. Solar competes directly. Each year it is supplying a bigger chunk of peak power needs in the middle of the day when air conditioners and factories are both at full throttle. “Demand during what was one of the most profitable times of the day disappears,” said the report. They cannot raise prices to claw back lost income. That would merely accelerate what they most fear. They are trapped.

Michael Liebreich, from Bloomberg New Energy Finance, says we can already discern the moment of “peak fossil fuels” around 2030, the tipping point when the world starts using less coal, oil and gas in absolute terms, but because they cannot compete, not because they are running out.

This is a remarkable twist of history. Just six years ago we faced an oil shock with crude trading at $148. The rise of “Chindia” and the sudden inclusion of 2bn consumers into the affluent world seemed to be taxing resources to breaking point. Now we can imagine how China will fuel its future fleet of 400m vehicles. Many may be electric, charged by PV modules.

For Germany it is a bitter-sweet vindication. The country sank €100bn into feed-in tariffs or in solar companies that blazed the trail, did us all a favour, and mostly went bankrupt, displaced by copy-cat competitors in China. The Germans have the world’s biggest solar infrastructure, but latecomers can now tap futuristic technology.

For Britain it offers a reprieve after 20 years of energy drift. Yet the possibility of global energy deflation raises a quandary: should the country lock into more nuclear power stations with strike-prices fixed for 35 years? Should it spend £100bn on offshore wind when imported LNG might be cheaper long hence?

For the world it portends a once-in-a-century upset of the geostrategic order. Sheikh Ahmed-Zaki Yamani, the veteran Saudi oil minister, saw the writing on the wall long ago. “Thirty years from now there will be a huge amount of oil – and no buyers. Oil will be left in the ground. The Stone Age came to an end, not because we had a lack of stones, and the oil age will come to an end not because we have a lack of oil,” he told The Telegraph in 2000. Wise old owl.

Read more: