Beneath a sky made opaque by billowing dust, a mechanised shovel driver steered his vehicle toward the vast wall of an open coal mine. It was the middle of a central Indian summer afternoon, and outside, the temperature had hit 45C. Up in the cab, 15 metres above the black, shiny ground, it was comfortable, air-conditioned.

The driver tipped the steel-toothed rim of the shovel’s bucket downwards, then slammed it into the coal seam wall in front of him. A few hours earlier, a drilling rig mounted on caterpillar tracks had drilled deep holes into the coal from the flat ground above, and filled them with explosives. Their detonation broke the coal into diggable chunks, some of them pebbles, others a metre across.

The seam being worked was 20 metres thick, and lay some 300 metres beneath what was once the ground’s surface – the deeper of two black stripes of coal. Overlying the seams, until it was blasted and dug away, were much larger quantities of grey-brown shale, what miners call “overburden”. Having been stripped from the coal, it lay stacked up in mountainous piles on either side of the mine, the walls of an artificial Grand Canyon. The surface area of this mine, Dudhichua, is 16 square kilometres.

In the year ending March 2015, Dudhichua produced 15m tonnes of coal – more than the UK’s entire remaining production. But it is only one of 16 mines in the Singrauli coalfield, which spans parts of two districts in Madhya Pradesh and Uttar Pradesh. All but one are owned by the state-run Northern Coalfields Ltd, a subsidiary of Coal India, one of the country’s biggest firms. As is the case with other Indian coalfields, Singrauli is home to numerous coal-fired thermal electricity plants, some almost on the doorstep of the mines. Their current aggregate capacity is about 20 gigawatts, nearly 10% of India’s total national generating capacity. (By comparison, peak electricity demand for the entire UK is only 57GW.)

Singrauli may be one of India’s biggest energy hubs, but it is also isolated. Apart from the mines and power stations, the coalfield is home to a handful of towns, poverty-stricken villages and some prosperous corporate “colonies”, with their own schools, sports fields and clinics. To visit the area involves a 220km drive from the nearest airport at Varanasi, on a chaotic road that often lacks a proper surface: the journey can easily take eight hours. Phone signals and internet are intermittent. The only communications that really work are the high-voltage power lines that carry Singrauli’s output to the teeming cities of northern India’s plains. Last year, the coalfield’s total production was about 87m tonnes. (When the British coal industry began to decline with the outbreak of the 1984 miners’ strike, it was producing about 130m tonnes annually.)

Singrauli’s significance – and that of the subcontinent’s many other coalfields, which span the length and breadth of India, with further large reserves in Pakistan – extends globally. In 2013, the UN Intergovernmental Panel on Climate Change (IPCC) reported that in order to restrict the increase of world average temperatures to 2C above pre-industrial times, the world must adopt a strict “carbon budget” for emissions. According to the IPCC, the current rate of fossil fuel burning will exhaust this within 25 years, after which fuels must either be left unexploited, or have their emissions kept from the atmosphere by carbon capture and storage.

India has the world’s fifth-largest coal reserves – and very few cleaner fossil fuels, such as natural gas. Its leaders are also determined to spread the benefits of economic development more widely among its population of almost 1.3bn people – one third of whom still have no access to electricity.

Anil Swarup, the permanent secretary at the coal ministry in Delhi, said in an interview that last year Indian production from both private and state-owned mines was 620m tonnes, more than 85% of it from open-cast workings. A further 400m tonnes were imported. At Singrauli and elsewhere, he added, production is set to increase rapidly, with strong encouragement from the rightwing Bharatiya Janata Party (BJP) government of Prime Minister Narendra Modi, which swept to power last year. Modi is determined to restore the sustained GDP growth rate of 8-10% that India enjoyed for a decade until 2011.

Mining overburden in the Singrauli coalfield. Photograph: Greenpeace/Sudhanshu Malhotra

“We are looking to double Indian coal production by 2020,” Swarup said, “and to reduce reliance on imports.” Beyond that date, he said production would continue to rise to 1.5bn tonnes a year, with most of this being burnt in coal-fired power plants. In the past six months, the government has given environmental clearance to 41 new mining projects. The consequence, Swarup said, is that from now until 2020, “a new mine will be opened every month. You have to work on the assumption of requirement, and in India, there is a need for power.”

Last August, the Indian supreme court ruled that more than 200 mining licences awarded by governments before 2010 were illegal, forcing the cancellation of numerous planned projects. The system that its judgment set aside had already been shown to be rife with corruption. The most prominent casualty of India’s “Coalgate” scandal was the former Congress prime minister Manmohan Singh, who last month came close to criminal indictment.

Enshrined in a law enacted by Modi’s government is a new scheme under which coal blocks are auctioned to the highest bidder. It hugely incentivises state governments to foster new mines. According to Swarup, the auctions of the 209 blocks that have been sold off to date have raised about £17bn – money that will swell state coffers for the next 30 years: “This will change the states’ economies. They were really strapped for money. Now they will get it.”

Many of the richest untapped reserves lie in heavily forested areas, some near Singrauli in Madhya Pradesh, but mainly in Chattisgarh and Jharkand in central India. There, those whose land will be subject to “acquisition” are some of India’s poorest inhabitants, many of them Adivasis – members of indigenous tribes.

Swarup insisted that preserving the environment was a high priority for those overseeing India’s new coal boom. “Seeing how the environment can be maintained is a crucial part of this. Whenever I talk to my officers, I say the environment is non-negotiable. But there is no viable alternative to developing more coal. Energy requirements have to be met.”

To many western environmentalists, who are determined to see a binding global deal to reduce greenhouse gas emissions at the UN climate change conference in Paris later this year, India’s rising coal use is anathema. However, across a broad range of Delhi politicians and policymakers there is near unanimity. There is, they say, simply no possibility that at this stage in its development India will agree to any form of emissions cap, let alone a cut. Even a pledge of the kind made by China’s leader Xi Jinping after talks with US president Barack Obama last year, that Chinese emissions would rise to a peak in 2030 and thereafter decline, would be out of the question.

This issue – the balance between the environment and growth – arises in every developing country. But India’s sheer size means that its resolution is of exceptional significance.

Modi has spoken repeatedly of India’s “right to growth”. Prakash Javadekar, the cabinet minister responsible for the environment, forests and climate change, enlarged on this in blunt terms, speaking in his office at the Rajya Sabha, the upper house of India’s parliament: “Our emissions will grow because we are not developed and we have a right, every person on this Earth has a right, to develop. If today the world is 0.8C warmer [than it was in pre-industrial times], it is not my fault. It is the historical responsibility of those who started emitting with the industrial revolution.” (However, largely because of its sheer size and population, India is one of the ten biggest historical emitters, having contributed around 7% to the warming the world has seen so far, compared to 20% for the US and 5% for the UK.)

He cited a Hindi political slogan, taken up by the BJP in its struggle to eclipse the once-impregnable Congress Party: “Singhasan khali karo ki janata aati hai,” which roughly means “Vacate the throne, the people are coming.” In Javadekar’s view, for now and for years to come, responsibility for reducing global emissions must be borne by the west: “They must vacate the carbon space because we are coming. We are developing.”

Underlying that insistence are some brutal facts. India is famously the world’s largest democracy, and is often said to possess the world’s biggest “middle class”. But in India this term has a meaning very different to its usage in the west. Navroz Dubash, the head of the climate initiative at Delhi’s Centre for Policy Research, pointed out that among the richest 10% of Indians, a third live in households which have no refrigerators. In the next richest 10%, only 45% have refrigerators, and in the 10% after that, only 28%. At the mid-point of India’s income distribution, the proportion of fridge owners is just 10%.

Among the richest 10% of Indians, a third live in households which have no refrigerators

Dubash, a lead author of the IPCC’s reports, is personally in no doubt as to the need to reduce global emissions. But he said that the limited reach of refrigerators – which India’s climate would seem to make indispensable – “tells you scary things. If you ask people with that level of access to energy to tighten their belts, that’s a very big ask. It means that emissions inevitably have to grow.” In India, he added, the number of people who consume as much energy as anyone deemed to be above the official poverty line in the developed world is, at most, a few tens of millions. Everyone else consumes less. “From a global perspective, you have to give India carbon headroom.”

Dubash is the principal author of a recent report that examines seven separate projections of India’s future energy needs and likely emissions. All of them – from institutions including government departments, the World Bank and TERI, the Energy and Resources Institute headed until recently by Raj Pachauri, the former IPCC chairman – state that both coal-fired power and Indian greenhouse gas emissions are set to increase substantially.

“By 2030, coal use is projected … to be 2.5-three times current levels,” the report says. Even with stringent policy action to increase the deployment of renewables and increase energy efficiency, “coal use is projected by all but one study to be more than two times current levels”. (Although India has a small nuclear industry – which provides less than 5% of its electricity – attempts to expand it have met strong political resistance. Any new nuclear capacity would take years to build and bring online, so it cannot be expected to fill the country’s energy needs any time soon.)

The consequence is that if, as the projections suggest, India’s emissions grow between two and three times by 2030, “India could be the second largest global emitter within the next decade.” Its projected output – between 4bn and 5.7bn tonnes of carbon dioxide each year – will surpass that of the US, which in 2011 was 5.3bn tonnes and falling, and be smaller only than China’s.

India’s population is set to outstrip China’s by 2028. But while its total emissions will be high, they will be nowhere near as great, on a per capita basis, as those of more developed countries. The Xi–Obama deal was based on the notion that by 2030, the two nations will reach per capita emissions “convergence”, with each person responsible for producing 14 tonnes of carbon each year. By that date, Prakash Javadekar said, the figure for the average Indian will be just 4 tonnes, a little over twice as much as today: “India will never reach the Chinese-American convergence point. Every climate action has a cost, but I can’t tax my poor.” Even in 2030, Indian per capita emissions are expected to remain below the current world average.

Dubash’s report regards all the projections as flawed: they tend to assume sustained high GDP growth, which may not be achievable, and there is a wide divergence between them. “We don’t have a very solid set of analytical inputs, and the projections are not robust,” Dubash said. For that reason alone, “stringent pledges would be unwise, because there is too much uncertainty”.

Similar opinions can be found in Delhi among people of very different political stripes. There are a few dissenters, such as Greenpeace India – which led a campaign by local people to resist the development of a new mine in Singrauli that was finally cancelled last year. Since then, the government has taken steps to curb its activities, freezing all its bank accounts on the grounds that it received donations from abroad. But Greenpeace remains on the margins of India’s debate.

According to Barun Mitra, the director of the Liberty Institute, a free-market think tank, “in a country where a third of the population doesn’t have electricity, binding emissions limits are a fairy tale”.

Nitin Desai is a retired UN diplomat, who organised the 1992 Earth Summit in Rio de Janeiro and later represented the UN secretary-general at international climate conferences. He is now a member of a small expert panel advising Modi in the lead-up to Paris. “In a country with blackouts and so many people without access to electricity, can I really manage without developing more coal?” he asked. “Why should we be accountable? The pressure should be on the countries whose per capita emissions are much higher. If you try to force India to adopt emissions targets, you will fail.”

The last time US and European leaders made a serious push for a binding global deal, at the 2009 climate conference in Copenhagen, India’s delegation was led by Jairam Ramesh, who did Javedekar’s job in the then-Congress-led government. As a minister, he was mercilessly attacked for holding up development on environmental grounds. He said: “The idea that India can set targets in Paris is completely ridiculous and unrealistic. It will not happen. This is a difficult concept for eco-fundamentalists, and I say this as a guy who is considered in India to be very green.”

Copenhagen, he said, failed because of what he termed “climate evangelism. I was sitting for days with Gordon Brown, Ed Miliband, Angela Merkel, Barack Obama and Sarkozy. It was absolutely bizarre. It failed because of an excess of evangelical zeal, of which Brown was the chief proponent. It should not happen again.”

He added: “Even with the most aggressive strategy on nuclear, wind, hydro and solar, coal will still provide 55% of electricity consumption by 2030, which means coal consumption will be 2.5 or three times higher than at present. Mining and burning coal imposes huge environmental burdens. It’s a double whammy: the more coal we extract, the more forest we lose, and that too will add to global warming.”

Nevertheless, he concluded, “I don’t see any alternative other than at least to double India’s coal consumption in the next 15 years.”

* * *

In Singrauli, the “environmental burdens” imposed by mining and burning coal are not difficult to spot.

Some of the area’s power stations date back to the 1970s, and their chimneys, which are almost 300m high, belch great plumes of thick, oily smoke. Coal power station chimneys are supposed to be fitted with electrostatic precipitators, devices to stop ash being emitted into the atmosphere. But Singrauli coal’s ash content is high, up to 40%, and the people who live in the shadow of the older plants say houses, vehicles and other exposed surfaces will often be coated in a thick, grey film.

Children play out side their houses in Simplex, a concrete shanty town adjoining the perimeter wall of the 4.7GW Vindhyachal power plant – one of the biggest in India. Photograph: Ritesh Shukla

“No one dries their washing outside round here,” said Dr KK Aggarwal, who runs a clinic in the town of Anpara, the site of four big plants, two of them old and two extremely new – the newest, Anpara D, began to come on stream this month. “Many of my patients suffer from respiratory problems, such as asthma, nasal conditions, bronchitis, and chronic obstructive pulmonary disease. There are also skin conditions such as eczema and psoriasis.” He is convinced the incidence of such conditions is higher than it should be because of the mines and power plants. “Pollution is everywhere.”

Some of Singrauli’s mine and power plant operators have already taken elaborate steps to reduce discharges into the air and water. Gigantic water sprayers and closed conveyor belts carrying coal from mine to power station keep dust to a minimum. The chimneys at the newest stations, Anpara C and D, and the nearby “super critical” plant run by the private firm Reliance, India’s biggest company, emit no visible smoke at all – and use only three-quarters as much coal as older stations.

Elsewhere, however, the noxious odour of coal dust hangs in the air, and after a few minutes outside, one senses gritty particles in the recesses of one’s mouth and throat. Some of the mines still ship their coal in open trucks, coating roadside trees, ground and buildings in layers of black grime. One of the worst places is the huge yard on the outskirts of Singrauli town, where loads are transferred from the trucks to railway wagons. At the yard entrance there’s a mini-roundabout, adorned with a seven-metre sculpture of a clenched fist, a monument to India’s trade unions. The fist, once red, is stained the deepest black.

Since 2010, the Indian government has designated Singrauli a “critically polluted area”. In 2012, Delhi’s prestigious Centre for Science and Environment (CSE) tested Singrauli’s water supplies, along with fish from local reservoirs, human blood and hair samples. In all, the study found high levels of mercury: in one village, water from pumps contained 26 times the maximum safe limit laid down by the Bureau of Indian Standards. Some of the hair samples had five times the “safe” concentration, while the fish contained twice the recommended level.

The CSE study also found high incidences of vitiligo, shivers, impaired vision, and burning sensation in the limbs, all recognised effects of mercury. Continued exposure, the study reported, might lead to depression, memory loss, and kidney damage. Chandra Bushan, the CSE’s deputy director and one of the study’s authors, told me the source of the mercury was evident: “fly ash” from Singrauli’s power plants.

Fly ash has its uses – for example, in making cement. But for decades, untold thousands of tonnes have been collected from the chimneys, mixed with water and then discharged into the Singrauli environment in the form of grey slurry, left to dry and blow about in vast, open air “ash decks”.

Filthiest of all is the treatment of ash from Anpara A, commissioned in 1987, and Anpara B, which began to generate power seven years later. From the plants, a row of pipes carries the slurry to a series of huge ponds, where the ash is supposed to settle out. But the system does not work. From the third and final pond, the milky, polluted liquid tumbles over a grey cascade into the Rihand reservoir, the source of drinking water for the entire Singrauli region. Where the slurry meets the blue reservoir waters, there is a clear and visible boundary. Once the ash is in the reservoir, there is no way to get rid of it.

In one of the ponds, Ram Pri, a landless Adivasi, was up to his waist in liquid muck, sieving out the ash in order to decant it into 33kg bags, which are used to make cement. He said he gets paid Rs50 – about 50p – per bag, and by this perilous, toxic labour, can make Rs200–300 a day. His wife used to help him, “but she can’t any longer: her feet, her knees and ankles are all swollen. She’s not able to walk. Maybe that’s because of what’s in the water.”

His is not the only local family to have derived little benefit from the Singrauli coal and power boom. For more than 20 years, several thousand mainly Adivasi people have been living in Simplex, a concrete shanty town adjoining the perimeter wall of the 4.7GW Vindhyachal power plant – one of the biggest in India. The colony was built to house workers who built the plant’s early phases, and its high-voltage output lines run directly overhead.

Astonishingly, Simplex is still not connected to the electricity grid. Its first “reverse osmosis” water treatment unit opened only eight months ago. Until then, said Anjani Kumar Chaubey, a local activist, “we used to get severe gastric problems. The water we took from our handpumps made your skin sting, and in the monsoon, it contained worms. The whole of India gets electricity from this plant, but we are like the darkness around a candle. How can our children study? Sometimes, when there is a lot of wind, the whole area gets covered with ash. A lot of our people get sick.”

In Chilkantanbasti, where 7,000 people live close to a 35-year old coal plant at Shaktinagar, run by the state-owned National Thermal Power Corporation, there is electricity. But the air is some of the region’s dirtiest: “A man gets up here in the morning and he eats coal dust,” said Umar Kand, 19. “He goes to bed at night, and he’s eating coal dust still. If you put anything out anything out round here, it will have a film of ash within an hour.” The streets stink also of sewage: there is no sanitation, and despite a promise by NTPC two years ago, no water treatment unit. There are three public toilets, but none of them work. Kand shrugged: “We go in the forest.”

Chilkatanbasti is exposed to another hazard. There are now strict rules governing the landscaping and afforestation of mine overburden piles, which must be split into tiers and divided by broad, flat “benches”, with no slope steeper than 37 degrees. When a giant pile from the Kharia mine that looms over the village was created, these rules did not exist, and the result is a tottering brown mountain, its slopes strewn with boulders the size of cars, its surface deeply etched by the water channels that form each monsoon.

Water full of ash from Anpara thermal power station is discharged into the Rihand reservoir in Singrauli. Photograph: Ritesh Shukla

“When it rains, material comes down towards us,” said Renu, a local woman who preferred not to give her surname. “The police have even come to tell us we should evacuate our houses in case it slips. I’ve seen the rocks falling down the slopes. If it ever went altogether, it would be like a tsunami. But how can we leave our homes?”

* * *

Speaking to Time magazine earlier this month, Prime Minister Modi failed to answer a question as to whether India would agree any binding emissions curb in Paris. Instead, he waxed lyrical about Indians’ love for nature, a theme echoed by environment minister Javadekar, who insisted: “Growth and environmental protection are not against each other. We want a clean India, a green India. Clean air is our birthright” – a statement that any visitor to Delhi, which currently endures the world’s worst particulate air pollution, will appreciate.

Yet these may not be empty words. For among the BJP government’s most ambitious acts has been to quintuple the 2022 targets set for non-fossil energy by the previous regime, to 175GW – almost six times its current level. The most ambitious target of all is that for solar energy, which is meant to rise from just 3GW now to 100GW, in only seven years. No country has ever built solar at anything approaching this pace, and it would leave India with three times as much solar capacity as Germany – which over the course of decades, has deployed 38.5GW, much more than anywhere else in Europe, and more than twice as much as the United States. Many people, Dubash said, regard the target as “aspirational”: the sheer manufacturing requirement, likely to come at first mainly from China, is huge.

On the other hand, for very obvious reasons, photovoltaic solar energy is a much more viable proposition in India than it is in northern European countries such as Germany, or for that matter, Britain. A well-sited solar panel in India will produce energy up to 22% of the time, as against perhaps 8% in the UK.

Ratul Puri, chairman of Hindustan Powerprojects Ltd, a multibillion-pound company that has invested heavily in both coal and solar, pointed out that solar has a further local advantage: “Solar generation perfectly overlays the demand cycle.” In other words, the hot, dry and sunny months will see solar output peak, just as the demand for irrigation pumps, fans and air conditioning is also at its greatest. During the cooling monsoon, solar output plummets, but so does demand: there is no need for irrigation when it’s pouring with rain.

“Can we have 100% of energy in India from solar?” Puri asked. “No, because I still want to be able to turn on my lights at 9pm at night, when solar is generating nothing. But 15, 20% of our energy coming from solar: we can easily do this in the very near future.”

Even in fertile, intensely farmed states such as Punjab, 15% of the land is arid, and unsuitable for irrigation – but ideal for solar panels. Meanwhile, in distinct contrast to Germany or Britain, the levelised cost of solar energy per 1KW/hr unit, averaged out over 25 years, is already close to “grid parity”, simply because Indian solar panels are so much more productive. Government subsidies have in the past been provided for small-scale users – though these were recently cut, from 30% to 15% of installation costs, while only 15% those who deployed solar panels ever claimed them anyway. In India, even without subsidy, solar is becoming competitive with electricity from coal.

According to Puri, the price of solar electricity has fallen from Rs13 to Rs6.5 per 1KW/hr unit over the past five years – very close to the Rs6 cost of thermal power from coal. However, recent reforms to the finance of long-term infrastructure debt are reducing the gap still further. Puri added: “Everyone expects interest rates [currently a ruinous 10- 12%] to come down. If that happens, solar is going to hit grid parity, irrespective of any technical discoveries, within the next two years.”

A well-sited solar panel in India will produce energy up to 22% of the time, as against perhaps 8% in the UK

In the past five years, Puri’s balance sheet has been split, two to one, in favour of coal over renewables. He said that over the next five years, he intends to reverse that balance, with £1bn going to coal and close to £3bn to solar – making Hindustan Powerprojects easily India’s biggest renewables investor.

Behind that decision is the fact that during the growth slowdown after 2011, very few new coal power plants were commissioned, while most of the private power firms which have come to dominate the industry are financially “distressed”.

The reasons are complex. They partly stem from the chaotic and indebted state of the “discoms”, or distribution companies, the middlemen in India’s electricity industry, which buy power from generators and sell it to consumers. Artificially low tariffs imposed by state governments mean that discoms deliberately restrict supply, preferring to make power cuts than to increase their losses by selling power at prices below its purchase cost. There has also been a widespread failure to take action against rampant electricity theft in informal urban settlements. The upshot is that most coal plants are operating at only 60% capacity – for the time being, there is a surprising degree of slack in the system.

But Puri said that if the economy “does start to roar again” in the way that Modi intends, the country will face a serious power shortfall by 2017. Even if new coal plants started to be planned today, they would not avert this problem: it usually takes seven-to-10 years for a freshly conceived coal plant to become operational.

On the other hand, solar projects can typically be realised within 12 to 18 months. “The inactivity in commissioning new thermal plants over the last three years leaves India no choice but to go out and build solar capacity. That means India can overcome the crisis of electricity shortages, have cleaner air, have a more stable grid and go say nice things at the climate change negotiations in Paris.”

Without storage technology far in advance of what exists today, coal will still have to provide India’s “baseload”: lights and air conditioning at night; power for the factories Modi wants to see built. But beyond 2030, anything is possible. “I think the entire energy landscape is going to change in the next 30 years,” Puri said. “Storage is going to revolutionise it. I also think solar energy will become much cheaper than coal. So why would you build a coal thermal plant?”

There are other solar niches. The unreliability of India’s grid power means the country possesses a staggering 80GW of expensive, off-grid, liquid-fuel generating capacity, most from highly polluting diesel generators. Typically, consumers pay about Rs18 per unit for it when their grid power goes off – three times the usual price.

In Noida, a burgeoning satellite city on the outskirts of the Delhi megalopolis, Kushagara Nandan runs Sunsource Energy, a solar start-up. Educated in the US, he cut his teeth on a similar outfit based in New Jersey. Last year, Sunsource revenues quintupled, to £6m.

Part of his business is supplying rooftop units which, when the sun is shining, can fill the gap caused by grid outages far more cheaply than diesel: “We synchronise grid, diesel and solar together. In Delhi alone, the potential for rooftop solar is at least 1.5GW.” One of his projects, rated at 250KW, adorns the Habitat Centre, a complex that includes conference venues, auditoria, restaurants and art galleries. Another 500KW array has allowed a school to save 20% on its power bills.

Cheap, off-grid solar also has great potential in India’s vast rural hinterland. Last year, a solar project to desalinate briny ground water from wells and power irrigation pumps at a village in the southern state of Andhra Pradesh, which Sunsource helped develop with an Indian NGO, was given a Google Global Impact Challenge award. It worked so well that it has now been rolled out in five different villages.

Like Ratul Puri, Nandan is a businessman. He is in solar primarily to make money. He urged caution: “Unrealistic expectations must not be raised. It’s crucial to realise that solar must be part of the mix – it cannot substitute for other sources. For the foreseeable future, India doesn’t have a choice between coal and solar. It needs both.”

Pragmatism of this kind of now characterises other parts of Indian discourse over energy and the environment. There is, for example, little dispute that the pollution caused in earlier phases of mining and power generation at Singrauli is unacceptable. “There’s about 80GW – 40% of India’s capacity – that is either in such disrepair or so dirty that it needs to be replaced,” said Puri. “The open trucks transporting coal and so on are a short-term phenomenon. No one in their right mind would transport coal by truck.”

For the past two years, Ashwani Dubey, a Delhi lawyer who was brought up in Singrauli, has been fighting a case to force the mine and power plant operators to clean up their act in the National Green Tribunal, a powerful judicial body that rules on environmental matters. In written evidence to the court issued in March, India’s Central Pollution Control Board recommended stringent measures, including the end of ash discharge into the Rihand reservoir by 31 July, and much stricter monitoring of air and water quality. Where necessary, remedial measures should be taken within six months – to be funded on the “polluter pays principle”. Within a few months, the open coal trucks are supposed to be gone – replaced by a closed “merry-go-round” railway linking mines to power plants.

Northern Coalfields now has an environmental team in Singrauli, led by BK Sharma. As parts of the mines are worked out, it “back-fills” the overburden in an effort restore the landscape, and replants native species: “We are trying to recreate the forest, so that when we leave, it will merge into the ecology of the area,” Sharma said.

A worker cleans solar panels at the Azure Solar Plant in Gujarat, India. Photograph: Kuni Takahashi/Getty Images

It sounds utopian. But trees in central India grow fast, and on a visit to what was a part of the Nigahi mine, it was hard to distinguish between remediated pit and original forest. Meanwhile, following a Green Tribunal order, nine village water treatment units have been installed this year. By the end of June, a further 15 are meant to be operational.

There are further developments at the national level. Under the new mining law, a third of the money raised by the mining royalty – a 15% levy on all mine revenue, payable to state governments – must be given to communities in mine-affected areas, to be spent as they determine. The details have yet to be worked out. But according to Chandra Bushan of the Centre for Science and Environment, “this is a revolutionary development with huge implications for the entire developing world”.

It is to be applied immediately, to old mines and new, and should mean the “darkness around the candle” seen in places such as Simplex will end. “Singrauli could become one of the richest districts in the country,” said Bushan. “Now we must make sure the money is spent on the right things.”

Meanwhile, the government has just introduced new pollution standards for coal plant technology – as strict as any in the world. “You will no longer be able to burn coal cheaply and pollute,” said Bushan. Under these rules, old plants such as Shaktinagar and Anpara A will have to be scrapped.

Bushan warned that better regulations would not necessarily be enforced. “The arm of the law is not always long in India. But there are certain trends that are positive. I am impressed quite frankly with the Modi government on these issues. They’ve done more than I expected.”

Where does all this leave India in the run-up to Paris? According to Navroz Dubash, what India and other developing countries need are not rigid emissions targets, but programmes designed to “bend the curve” – to make emissions lower in the five years after 2020 than they would have been otherwise. The changing format of UN climate negotiations makes this easier to achieve. The diplomatic focus now is not on emissions targets but what are termed INDCs – each country’s “intended nationally determined contribution”. These, Dubash said, “provide an opportunity to dissolve the barrier between development and climate needs”.

Measures Dubash would like to see in India’s INDC include its targets for solar energy, better building standards, shifting freight from road to rail, low-energy ceiling fans, and widespread use of LEDs. Most are already in the pipeline: Javadekar said India is about to announce a massive plan to replace city street lights with low-energy LEDs.

That approach may allow India to plot the delicate course between environmental and developmental needs. “As an old UN hand, I must tell you that we only distinguish between success and outstanding success,” Nitin Desai joked. “2015 will be a success. The issue is how great it will be.”

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