Solar ‘ready to deliver’ as Labour proposes 2030 net zero target

Image: Getty

Solar is “ready to deliver” in the transition to a net zero future but the Labour Party is facing a “considerable challenge” in its proposed target of net zero by 2030.

This week the Labour Party approved a motion to adopt a Green New Deal, under which the party has pledged to commit to pursuing a net zero economy by 2030 in the event of a Labour majority in any prospective general election.

That target, some 20 years earlier than the current target, made legally binding four months ago, would make it the most ambitious and give the UK just eleven years to achieve the transition.

Chris Hewett, chief executive of the Solar Trade Association, said that whilst an earlier target is welcome, 2030 would be a “considerable challenge” due to the practicalities of decarbonising “more difficult sectors” such as transport and heat.

Hewett also stressed the importance of utilising solar and battery storage in the transition, which will play a “vital role” over the next decade, in particular as costs are set to continue to fall in the period.

“Solar can be deployed very quickly and has already demonstrated it can do this at scale. The industry stands ready to deliver,” he said.

The Labour Party has shown an interest in supporting solar in recent months, having revealed in May plans to install solar on 1.75 million homes. This ambition was positively received from the industry, described as “the leadership we need on renewables”.

And at last year’s annual conference, the party announced it would look to treble the UK’s solar capacity by 2030 as part of a Labour government.

Hewett lauded this commitment as one which would make “a significant contribution towards the decarbonisation of our grid”.

However, a whole range of clean power sources will be needed to meet net zero within “any timeframe”, RenewableUK’s Luke Clark said.

“We need to rapidly ramp up all of our clean power sources, including onshore wind and innovative renewable technologies, to unlock decarbonisation right across our economy.

“Increased investment in renewable energy will create thousands of jobs across the UK and bring huge benefits to local economies,” Clark continued, adding that offshore wind will be “key” due to its record results in the latest Contracts for Difference auction.

Global renewable energy initiative aims to bring a billion people in from the dark

Worldwide commission aims to end energy poverty in sub-Saharan Africa and south Asia by driving investment in new technology

A woman runs her takeaway restaurant by candlelight during a scheduled power outage in the impoverished neighbourhood of Masiphumelele, Cape Town
A woman runs her takeaway restaurant by candlelight during a scheduled power outage in the impoverished neighbourhood of Masiphumelele, Cape Town. Photograph: Nic Bothma/EPA

Electricity could be delivered to more than a billion people currently living without it within a decade by linking up small-scale projects into a giant, environmentally-friendly network.

According to a new global commission, advances in micro energy grids and renewable energy technologies could “dramatically accelerate change” and transform lives in rural areas of sub-Saharan African and south Asia.

The Global Commission to End Energy Poverty met for the first time this week to set out plans to accelerate the UN’s sustainable development goal to ensure access to affordable, reliable and sustainable energy for all people by 2030.

The commission, established by the Massachusetts Institute of Technology Energy Initiative and the Rockefeller Foundation, plans to bring together leading investors, utilities and policymakers to tackle energy poverty.

Under the initiative, the distributed networks would help connect homes, businesses and schools to small-scale solar power projects to deliver cheap, sustainable electricity that can help power local economic growth.

The commission includes government leaders, energy industry chief executives and representatives from major development organisations, including Fatih Birol, the head of the International Energy Agency.

Dr Rajiv Shah, president of the Rockefeller Foundation and formerly of the US agency for international development, said “a whole new way of thinking” about energy distribution was required.

“We cannot end poverty without successfully ending energy poverty,” said Shah.

“For 140 years we’ve had this mindset that energy access means building big power plants and connecting them to grids, and that’s how you provide electricity.

“Today, new technology frontiers, business models, and our knowledge of alternatives is so strong that this commission will be able to set out a new roadmap to end the energy access problem for 1 billion people across the globe.”

The commission also plans to help set up new regulation in developing countries to accelerate the rollout of new energy systems, and make the projects more attractive to international investors.

“If I want to start a small solar-powered mini-grid programme in a rural part of an under-served country, I could be prevented from actually providing power without permission from the state-owned utility which might own that business opportunity,” Shah explained.

“That’s one of many policy roadblocks that is preventing distributed solutions from really being easy to invest in.”

Shah will co-chair the commission alongside Dr Ernest Moniz, a former US energy secretary,and Dr Akinwumi Adesina, the president of the African Development Bank.

Moniz warned that existing plans to end global energy poverty by 2030 are “not fast enough” and should be more ambitious.

“Twenty years ago, energy access might have been defined by having a 20-watt lightbulb. One doesn’t want to denigrate that – the shift from having no light to some light is major – but our ambition is more than that. We want energy access that allows for credible family, community and regional economic development. Frankly, we’d like it to allow for entrepreneurial activity too,” he said.

Moniz said that by relying on renewable energy, particularly solar power alongside batteries, developing nations should be able to attract investment in clean energy and rule out the need for future investments in coal-fired power plants. Adopting such methods could also halt the wood-burning that has led to mass deforestation in some countries, he said.

“Speaking personally, there is a lot of concern about a new round of investments in coal funded by Chinese development banks. There could be a lock-in of emissions for the future. We would rather see distributed [energy grid] architecture, including renewables, and potentially with a role for gas,” he said.

Shah added that economic development and the empowerment of women offered the best chance for a low-emissions future.

“If you’re a woman in rural Bihar and you’re able to all of a sudden access electricity, get a sewing machine, create an income, provide light for your daughter to study at night, it’s just transformational,” said Shah.

“We’ve seen the same thing in India and Myanmar and throughout Africa. This commission embarks upon this task with a huge amount of optimism and a real understanding of how important it is in the lives of so many people around the world.”

 

 

 

Wyelands eyeing early-mover status in UK subsidy-free solar finance rush

Wyelands Bank has set its sights on becoming one of the early movers in subsidy-free solar finance in the UK, investing in a range of projects in a bid to stimulate the market.

Late last month the bank collaborated with renewables developer Anesco and research firm Aurora Energy Research on a new report which claimed that co-located solar-plus-storage projects could deliver investors internal rates of return of around 7.6% as early as next year, a rate which would render a large number of potential developments attractive enough for financiers.

Jim Higginbotham, managing director, asset finance at Wyelands, told Solar Power Portal that the report was actually “fairly conservative” with its estimates, stating that the demand for flexible solar and storage assets in the UK was “inescapable”.

This, Higginbotham said, was a result of the sector’s experience of merchant solar farms and the availability of real-world data which had resulted in greater predictability over revenues and returns.

Nevertheless, it was still considered that most investors would need a “leap of faith” to finance a subsidy-free project in the UK, a leap that “most organisations aren’t prepared to take”. He added that most organizations were finding it hard to “recalibrate their risk appetite” to what is a completely different marketplace in unsubsidised renewables.

Higginbotham said that Wyelands was, however, prepared to take that leap and wanted to become one of the early movers in the space.

Wyelands is keen to invest in subsidy-free solar farms, providing up to £15 million in investment per project. That is expected to support developments in the 10-20MW capacity range, providing around 30 – 35% of the up-front capital cost of certain projects.

It’s part of a wider push into renewables from Wyelands as part of an overall growth plan, with Higginbotham adding that there was “no lack of appetite” to support the marketplace.

“[We’re] never going to be the most predominant lender, but I’d like to be known as a supporter of the industry and the sector. The more people and banks like Wyelands, it will build confidence for the bigger, high street lenders to come into the marketplace.

“If us going first can build the roadway for others to come in and support the industry, then that’s great news as far as I’m concerned. We want to be one of those first movers that starts the momentum,” he said.

EDF switches off Cottam coal-fired power station for last time

EDF Energy has shut down Cottam power station in Nottinghamshire.

Since it started generating in 1968, EDF states the 2GW power station had burnt some 183m tonnes of coal to generate 500 terawatt hours of electricity across 1.1m generation hours.

Around 140 people currently work at the site.

Cottam’s plant manager Andy Powell, who joined the site as an apprentice, said: “Since the official announcement of the site’s closure earlier in the year we have been working with the Cottam team to ensure they secure the right future for them.”

According to the company, some will work on the new nuclear power station at Hinkley Point. Others will work at West Burton A coal station which has capacity market contracts to operate until September 2021, or at West Burton B Combined Cycle Gas Turbine station which started operating in 2013.

The UK’s remaining coal plants are set to shut down over the next few years.

RWE will close the 1.56GW Aberthaw B in March, while SSE’s 1.5GW Fiddler’s Ferry is set to close at the same time.

The closures will leave Uniper’s 2GW Ratcliffe on Soar, Drax’s remaining coal units (1.3GW) and EDF’s 2GW West Burton A plants as the last standing GB coal stations.

Related stories:

RWE to shut Aberthaw B coal plant

Capacity Market: Sara Bell on what happens next

Capacity Market clears at 77p

SSE to close Fiddler’s Ferry

Drax and Iberdrola agree Capacity Market risk share to get deal over line

UK facing massive power shortages when coal stations close, warn engineers

The World’s Oceans Are in Danger, Major Climate Change Report Warns

The warming world is disrupting aquatic life and ocean patterns, with dire global consequences.
CreditCreditScott McIntyre for The 

WASHINGTON — Climate change is heating the oceans and altering their chemistry so dramatically that it is threatening seafood supplies, fueling cyclones and floods and posing profound risks to the hundreds of millions of people living along the coasts, according to a sweeping United Nations report issued Wednesday.

The report concludes that the world’s oceans and ice sheets are under such severe stress that the fallout could prove difficult for humans to contain without steep reductions in greenhouse gas emissions. Fish populations are already declining in many regions as warming waters throw marine ecosystems into disarray, according to the report by the Intergovernmental Panel on Climate Change, a group of scientists convened by the United Nations to guide world leaders in policymaking.

“The oceans are sending us so many warning signals that we need to get emissions under control,” said Hans-Otto Pörtner, a marine biologist at the Alfred Wegener Institute in Germany and a lead author of the report. “Ecosystems are changing, food webs are changing, fish stocks are changing, and this turmoil is affecting humans.”

Hotter ocean temperatures, combined with rising sea levels, further imperil coastal regions, the report says, worsening a phenomenon that is already contributing to storms like Hurricane Harvey, which devastated Houston two years ago.

For decades, the oceans have served as a crucial buffer against global warming, soaking up roughly a quarter of the carbon dioxide that humans emit from power plants, factories and cars, and absorbing more than 90 percent of the excess heat trapped on Earth by carbon dioxide and other greenhouse gases. Without that protection, the land would be heating much more rapidly.

But the oceans themselves are becoming hotter, more acidic and less oxygen-rich as a result, according to the report. If humans keep pumping greenhouse gases into the atmosphere at an increasing rate,marine ecosystems already facing threats from seaborne plastic waste, unsustainable fishing practices and other man-made stresses will be further strained.

“We are an ocean world, run and regulated by a single ocean, and we are pushing that life support system to its very limits through heating, deoxygenation and acidification,” said Dan Laffoley of the International Union for Conservation of Nature, a leading environmental group that tracks the status of plant and animal species, in response to the report.

The report, which was written by more than 100 international experts and is based on more than 7,000 studies, represents the most extensive look to date at the effects of climate change on oceans, ice sheets, mountain snowpack and permafrost.

CreditNatalija Gormalova/Agence France-Presse — Getty Images

Prince Harry supports Greta Thunberg’s climate ‘strikes’

Prince Harry with a child planting trees

The Duke of Sussex has defended climate change activism led by Swedish campaigner Greta Thunberg, calling the effort “a race against time”.

“Everyone knows it… no-one can deny science,” Prince Harry added.

Several million people took part in so-called “strikes” led by schoolchildren around the world on Friday.

Prince Harry also said Botswana, which he is visiting on a tour of southern Africa, had been a place to “get away from it all” after his mother’s death.

He said he had visited the country soon after Diana, Princess of Wales, died in August 1997 and had made “some of his closest friends” there.

“Now I feel deeply connected to this place and to Africa,” he said during a visit to the Chobe Tree Reserve.

The prince has been helping to plant trees on the banks of the Chobe River following decades of deforestation and was greeted by his friend Dr Mike Chase, a conservationist working with locals to develop the site into a nature and cultural reserve.

“This last week, led by Greta, the world’s children are striking,” the prince said.

“It’s a race against time and one in which we are losing. Everyone knows it, there’s no excuse for not knowing that.”

He went on to say there had been scientific evidence of climate change for at least 30 years.

“And it’s only getting stronger and stronger,” he added.

Can solar power shake up the energy market?

Socrates

The classical Greek philosopher Socrates believed the ideal house should be warm in winter and cool in summer. With clarity of thought like that, it’s easy to see how the great man got his reputation.

At the time, such a desire was easier to state than to achieve, yet many pre-modern civilisations designed buildings to capture sunlight from the low-hanging winter sun, while maximising shade in the summer.

All very elegant but that’s not the sort of solar power that will run a modern industrial economy. And millennia went by without much progress.

A Golden Thread, a history of our relationship with the sun published in 1980, celebrates clever uses of solar architecture and technology across the centuries, and urged modern economies wracked by the oil shocks of the 1970s to learn from the wisdom of the ancients.

Oia village in Santorini, Greece, in July 2018

For example, parabolic mirrors – used in China 3,000 years ago – could focus the Sun’s rays to grill meat.

Solar thermal systems used winter sun to warm air or water that could reduce heating bills.

Such systems now meet about 1% of global energy demand for heating. It’s better than nothing, but hardly a solar revolution.

A Golden Thread only briefly mentions what was, in 1980, a niche technology: the solar photovoltaic (PV) cell, which uses sunlight to generate electricity.

The photovoltaic effect isn’t new. It was discovered in 1839 by French scientist Edmond Becquerel, when he was just 19.

Edmond BecquerelImage copyrightGETTY IMAGES
Image captionBecquerel first observed the photovoltaic effect in his father’s laboratory

In 1883, American engineer Charles Fritts built the first solid-state photovoltaic cells, and then the first rooftop solar array which combined different cells, in New York city.

These early cells – made from a costly element named selenium – were expensive and inefficient.

The physicists of the day had no real idea how they worked – that required the insight of a fellow named Albert Einstein in 1905.

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Programme image for 50 Things That Made the Modern Economy

50 Things That Made the Modern Economy highlights the inventions, ideas and innovations that helped create the economic world.

It is broadcast on the BBC World Service. You can find more information about the programme’s sources and listen to all the episodes online or subscribe to the programme podcast.

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But it wasn’t until 1954 that scientists at Bell Labs in the US made a serendipitous breakthrough.

By pure luck, they noticed that when silicon components were exposed to sunlight, they started generating an electric current. Unlike selenium, silicon is cheap – and Bell Labs’ researchers reckoned it was also 15 times more efficient.

These new silicon PV cells were great for satellites – the American satellite Vanguard 1 was the first to use them, carrying six solar panels into orbit in 1958.

The Vanguard 1 satelliteImage copyrightNASA

The Sun always shines in space, and what else are you going to use to power a multimillion-dollar satellite, anyway? Yet solar PV had few heavy-duty applications on Earth itself: it was still far too costly.

Vanguard 1’s solar panels produced half a watt at a cost of countless thousands of dollars.

By the mid-1970s solar panels were down to $100 (£81) a watt – but that still meant $10,000 for enough panels to power a light bulb. Yet the cost kept dropping.

By 2016 it was 50 cents a watt and still falling fast. After millennia of slow progress, things have accelerated very suddenly.

Perhaps we should have seen this acceleration coming.

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More things that made the modern economy:

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In the 1930s, an American aeronautical engineer named TP Wright carefully observed aeroplane factories at work.

He published research demonstrating that the more often a particular type of aeroplane was assembled, the quicker and cheaper the next unit became.

Workers would gain experience, specialised tools would be developed, and ways to save time and material would be discovered.

Wright reckoned that every time accumulated production doubled, unit costs would fall by 15%. He called this phenomenon “the learning curve”.

Recently, a group of economists and mathematicians at Oxford University found convincing evidence of learning-curve effects across more than 50 different products from transistors to beer – including photovoltaic cells.

Sometimes the learning curve is shallow and sometimes it is steep, but it always seems to be there.

In the case of PV cells, it’s quite steep: for every doubling of output, cost falls by over 20%.

And this matters because output is increasing so fast: between 2010 and 2016 the world produced 100 times more solar cells than it had before 2010.

112,000 photovoltaic solar panels at the power plant in La Colle des Mees, Alpes de Haute Provence, south-eastern FranceImage copyrightGETTY IMAGES
Image captionThe power plant in La Colle des Mees, Alpes de Haute Provence, France, has 112,000 solar panels across 200 hectares

Batteries – an important parallel technology for solar PV – are also marching along a steep learning curve.

The learning curve creates a feedback loop that makes it harder to predict technological change. Popular products become cheap and cheaper products become popular.

And any new product needs somehow to get through the expensive early stages. Solar PV cells needed to be heavily subsidised at first – as they were in Germany for environmental reasons.

More recently China seems to have been willing to manufacture large quantities in order to master the technology.

This led the administration of previous US President Obama to complain that, rather than being too expensive, imported solar panels had become unfairly cheap.

Solar panels are particularly promising in poorer countries with underdeveloped and unreliable energy grids and plenty of sunshine during the day.

When Indian Prime Minister Narendra Modi assumed office in 2014, for example, he announced ambitious plans to build large utility-scale solar farms – but also to establish tiny grids in rural villages with little or no access to the main grid.

A worker installs solar panels at the Gujarat solar park in Patan, IndiaImage copyrightGETTY IMAGES
Image captionThe Indian government says the country receives more than enough solar radiation to meet its annual energy needs

But now that solar PV has marched along the learning curve, it is competitive even in rich, well-connected areas.

As early as 2012, PV projects in the sunny US states were signing deals to sell power at less than the price of electricity generated by fossil fuels.

That was the sign that solar power had become a serious threat to existing fossil fuel infrastructure, not because it’s green but because it’s cheap.

In late 2016 in Nevada, for example, several large casino chains switched from the state utility to purchase their power from largely renewable sources.

This wasn’t a corporate branding exercise: it was designed to save them money, even after paying $150m (£122m) as a severance fee.

The Sun does not shine at night, and winter storage remains a big challenge. As Socrates warned us: the wisest people understand that they know nothing.

But the learning curve tells us that the ultimate triumph of solar PV seems likely: it is getting cheaper as it gets more popular, and more popular as it gets cheaper.

Socrates notwithstanding, that sounds like a recipe for success.

Subsidy-free solar is coming of age

 

Subsidy-free solar energy has an important role to play in the decarbonisation of UK energy.  But its development has been hindered by a lack of confidence from investors who perceived too many risks for too little reward.

However, a new independent report suggests it is coming of age as an investment.  Co-locating new solar power with battery storage can reduce risks, create new revenues streams and ultimately unlock growth across the sector.

Why confidence matters

Good renewable energy investors do their homework and analyse the risks and rewards of any potential venture.  They then apply a confidence level to determine the appropriate balance of risk and reward that they are prepared to accept.

The greater the confidence in the desired outcome the less the perceived risk and the lower the return required to achieve the same risk and reward balance.

As more investors have increasing confidence in the future, more solar power and battery storage projects are undertaken which creates increased evidence on which new investors can justify their decisions. The virtuous circle continues to drive the industry forward.

Investing in subsidy-free solar

To understand the state of play with subsidy-free solar, Wyelands Bank, together with renewable energy firm Anesco, commissioned a study by Aurora Energy Research.  The research explores the economics of co-located solar power and battery storage sites.

The research shows that hybrid projects, where solar power and battery storage are co-located on the same site, are coming of age.

Hybrid systems are quickly becoming investable opportunities in the GB power system for equity investors and asset finance lenders – without any public subsidy.

Previously, uncertain returns have made it hard for solar and battery operators to raise debt finance.  They have also relied heavily on government subsidies which have been phased out for solar.  These two factors have combined in limiting the appeal to investors.

Looking forward, the report shows that co-locating solar power with battery storage can unlock additional revenue streams and accelerate deployment.

The research finds that internal rates of return (IRRs), or the measure of the likely profitability of an investment discounted over the life of the project, for hybrid projects deployed in 2020 are between 6.6% to 7.6% under Aurora’s central scenario assumptions.

This is compared to an overall IRR of just 4% for standalone solar and battery projects.

This could increase a further 2%-3% if more aggressive but still feasible market assumptions are used.  Higher potential returns should make it easier for co-located solar power and battery storage to attract funding.

Reducing risks and increasing revenues

Why does co-locating solar power with battery storage increase investor confidence?

First, co-locating solar power and battery storage reduces the risk of price cannibalisation.

Battery storage provides a hedge against the high deployment of solar capacity which leads to lower capture prices for all solar assets.

Next, the research finds that co-locating solar with battery storage may unlock further savings and revenues streams.

Co-locating solar and battery storage assets can generate significant overhead savings including but not limited to lease and network connection costs

Battery storage also allows for the avoidance of energy spilling where the solar capacity is higher than the grid connection. Reducing spilling leads to higher revenues.

How Wyelands Bank can help

At Wyelands Bank we have an appetite to support such co-located solar battery sites by providing senior debt.

Dependent on available cash flows leverage levels of around 35% of the build cost are possible with debt priced typically below the unleveraged project internal rate of return.

This means that not only can investors release a proportion of their equity in such sites, they can also benefit from increased leveraged project IRRs.

Wyelands Bank takes a straightforward solutions-focussed approach when assessing these opportunities.  We look at the macro factors influencing the future market and take a pragmatic view as to what a realistic downside case might look like.

Most industry commentators would agree that in order to reach the agreed UK government target of net zero greenhouse gas emissions by 2050 more subsidy-free solar is required.

We believe co-locating solar power and battery storage has the potential to reduce the risks, increase revenues and ultimately unlock growth in solar power.

This is because co-location limits the downside case and provides confidence that the business model underpinning such investments will remain intact and relevant for many years to come.

In a world where our ecological survival hangs in a delicate balance, I personally have confidence that we can make a difference.

At Wyelands Bank we are proud to be part of the solution not the problem.

York set for 400kW ‘HyperHub’ solar carport with storage

A solar carport backed up with battery storage is set to be built in York as part of its ‘HyperHubs’ project.

The solar carport has a proposed generation capacity of up to 400kW, powering a mix of 160kW and 7kW electric vehicle (EV) chargers.

The solar for the eight ultra rapid chargers is to be located on canopies located over 254 parking spaces in the adjacent Park and Ride car park, with solar also going onto canopies above the five 7kW chargers, which will service 10 parking bays.

A battery storage unit is also set to go onto the site to store any excess solar, with the solar expected to generate up to 380,000kWh of electricity per year.

The carport is the first in the HyperHubs element of the Go Ultra Low York Programme and will be located at the Park and Ride site at Monks Cross. A second site at Poppleton Bar has also gone into planning.

The HyperHubs project will see multiple hubs located around the outer ring road of York, with the aim of providing charging in the key traffic flow corridor and accelerate the uptake of EVs in the city by supporting fleets, residents, through traffic and visitors to have the confidence to use EVs.

This is according to the planning documents submitted by Arcus Consulting Services on behalf of the City of York council.

The plans are still subject to approval from the City of York Council. If approved, building will commence in January 2020 with an aim of completion in six months.

Northumberland County Council had similar plans for a 800kW solar carport with battery storage approved in July. However, local councils were this month warned they may face legal challenges if climate change plans are not implemented, with environmental law group ClientEarthdescribing it as a “collective failure”.

The long history of solar power

Socrates

The classical Greek philosopher Socrates believed the ideal house should be warm in winter and cool in summer. With clarity of thought like that, it’s easy to see how the great man got his reputation.

At the time, such a desire was easier to state than to achieve, yet many pre-modern civilisations designed buildings to capture sunlight from the low-hanging winter sun, while maximising shade in the summer.

All very elegant but that’s not the sort of solar power that will run a modern industrial economy. And millennia went by without much progress.

A Golden Thread, a history of our relationship with the sun published in 1980, celebrates clever uses of solar architecture and technology across the centuries, and urged modern economies wracked by the oil shocks of the 1970s to learn from the wisdom of the ancients.

Oia village in Santorini, Greece, in July 2018
Image captionBuildings in Santorini, Greece, are traditionally painted white to reflect the Sun’s rays

For example, parabolic mirrors – used in China 3,000 years ago – could focus the Sun’s rays to grill meat.

Solar thermal systems used winter sun to warm air or water that could reduce heating bills.

Such systems now meet about 1% of global energy demand for heating. It’s better than nothing, but hardly a solar revolution.

A Golden Thread only briefly mentions what was, in 1980, a niche technology: the solar photovoltaic (PV) cell, which uses sunlight to generate electricity.

The photovoltaic effect isn’t new. It was discovered in 1839 by French scientist Edmond Becquerel, when he was just 19.

Edmond Becquerel
Image captionBecquerel first observed the photovoltaic effect in his father’s laboratory

In 1883, American engineer Charles Fritts built the first solid-state photovoltaic cells, and then the first rooftop solar array which combined different cells, in New York city.

These early cells – made from a costly element named selenium – were expensive and inefficient.

The physicists of the day had no real idea how they worked – that required the insight of a fellow named Albert Einstein in 1905.

Presentational grey line
Programme image for 50 Things That Made the Modern Economy

50 Things That Made the Modern Economy highlights the inventions, ideas and innovations that helped create the economic world.

It is broadcast on the BBC World Service. You can find more information about the programme’s sources and listen to all the episodes online or subscribe to the programme podcast.

Presentational grey line

But it wasn’t until 1954 that scientists at Bell Labs in the US made a serendipitous breakthrough.

By pure luck, they noticed that when silicon components were exposed to sunlight, they started generating an electric current. Unlike selenium, silicon is cheap – and Bell Labs’ researchers reckoned it was also 15 times more efficient.

These new silicon PV cells were great for satellites – the American satellite Vanguard 1 was the first to use them, carrying six solar panels into orbit in 1958.

The Vanguard 1 satellite

The Sun always shines in space, and what else are you going to use to power a multimillion-dollar satellite, anyway? Yet solar PV had few heavy-duty applications on Earth itself: it was still far too costly.

Vanguard 1’s solar panels produced half a watt at a cost of countless thousands of dollars.

By the mid-1970s solar panels were down to $100 (£81) a watt – but that still meant $10,000 for enough panels to power a light bulb. Yet the cost kept dropping.

By 2016 it was 50 cents a watt and still falling fast. After millennia of slow progress, things have accelerated very suddenly.

Perhaps we should have seen this acceleration coming.