host: welcome to “global 3000”" ocean roamers -- a small community in costa rica is working to protect sea turtles. saving the past -- malaysia's construction boom is causing strife between heritage protection activists and mining interests. and a right to clean air -- people living in south africa's coal belt want an end to pollution.

the global energy crisis has given dirty coal plants a new lease of life. at least for the moment. but energy security concerns are driving the worldwide expansion of windfarms and solar parks too. the international energy agency, iea, expects that by 2027, global renewable power capacity will rise worldwide by 2400 gigawatts. that's roughly how much power china generated in total in 2022. in particular, china and the u.s. want to invest heavily in wind and solar energy, partly for climate protection reasons. in the u.s., a recently passed law earmarked almost $370 billion for climate and energy security measures. the eu and other countries are also keen to invest in renewable energy sources. the iea forecasts that by 2025, renewables will have become the largest source of global electricity generation, ahead

of coal. but there is some way to go. there are still more than 2400 coal-fired power plants in operation worldwide, with new ones being built. that's a huge burden both for the climate and those living nearby. reporter: south africa's economy is powered by coal. but critics say this comes at a massive cost. thomas: the science is there. air pollution is a killer and therefore the government needs to act urgently. promise: my heart is bleeding for the people who are living in this area. and they are getting poorer every day. reporter: 80% of the country's energy is produced by 12 coal-fired power stations in the south african coal belt. in 2019, green peace declared the area to be one of the most polluted on earth. duduzile: we are suffering every day.

we can't breathe. you even ask yourself whether you are going to wake up alive. you lie awake the whole night without sleeping because you can't breathe. reporter: dr. ndhlovu's practice in emalahleni is right in the coal belt. duduzile mkhwanazi is breathing heavily. while she has been having problems for years, the condition has worsened and she is concerned. dr. ndhlovu: there is lots of blasting, there are lots of mines around. the air is polluted, water is polluted, so obviously you are going to have lots of respiratory problems. quite often we get bronchitis, we do get chronic sinusitis, we do get asthma because of the environment as well. reporter: the mother of four has sent three of her children to other parts of the country because their health was poor. now she fears for herself. she works in building and road maintenance. duduzile:

there is no way i can do work like that. i have to sit down and take a break all the time. >> -- environmental justice group is celebrating a victory following judgment in the quote-unquote deadly air case. reporter: in 2022, the constitutional court ordered the government to enforce rules for polluters to meet minimum air quality standards. the judgment was celebrated as a landmark case. better air will only become a reality if less coal is burnt, but the industry employs almost 100,000 people. weaning itself off coal will have dramatic consequences. promise mabula, however, believes that a transition to green energy is vital. she runs vukani, a local environmental ngo. promise: the land. it's a mess. the water, the river that we

used to rely on. it's a mess. we started with raising awareness and hearing from communities' opinions on how do they want to see the future without coal. reporter: vukani is based in the outskirts of emalahleni. the ngo installed a solar system on its own roof to show that power production can be taken into the hands of the community. solar can be an opportunity for local job creation and healthier environments, according to vukani. it's a vision that mabula propagates with the community's youth. promise: for us, we are speaking of community grid that we want. an energy that will be a community-led where it will give space, especially for the young people, to create and manufacture for themselves, to make sure they put the solar pv

on the community rooftops. we have our own power station in blocks. reporter: but can solar really replace power plants? and how can communities finance their own green power? thomas mnguni deals with these questions. he works for groundwork, an organization that advocates for a just energy transition with new and better jobs, social justice, and poverty eradication. for mnguni, the costs of renewables cannot be compared to coal's irreplaceable human loss. a 2017 study commissioned by groundwork was an eye opener. thomas: the results indicated that about 2203 people are dying annually because of air pollution and more than 10,000 people are hospitalized because of respiratory problems. i think part of our constitution strikes the perfect balance between development and the

right to health. so, it's not an either/or situation. we can develop economically and at the same time taking care of people's health. reporter: for mkhwanazi, the transition cannot come quick enough. after picking up her daughter from kindergarten, she returns home. her electricity has gone. rolling outages are affecting the neighborhood up to three times a day. a bitter irony that those suffering from the pollution are the ones being cut from power. mkhwanazi and her daughter have gotten used to the dark. but there is always an uneasy feeling. duduzile: i am always afraid for my daughter. when the attack comes, you have to run to the clinic. the other day she was so sick, we had to go to the hospital. i had to pray to god to help her. reporter:

after spending five days in hospital, her daughter got better again. it's high time that the impact of air pollution on people's lives is recognized. host: by 2060, more than 70% of the world's population will likely live in cities or urban areas. there will also be around 10 billion people living on earth. that's two billion more than today. to accommodate this many people, millions of houses and apartments will have to be built. and of course, demand for energy and other supplies will also increase. according to oecd estimates, by 2060, global material consumption will reach around 167 gigatons -- so, about twice the current amount. that's the equivalent of more than 27,800 pyramids of giza. sand, gravel, and limestone are

in particularly high demand. with dramatic consequences. reporter: the descent into the cave, into the darkness. for ah tat, it's also an expedition into another world. and every time, it's an adventure, too. an adventure that leads back into the far-distant past. to the people who lived here 10,000 years ago. ah: we discovered this cave via the internet. we call it the “guaa-ajia” water cave. we were curious. we've explored the cave and we think it's really beautiful. unfortunately, it is right by one of the quarries. reporter: nearby, limestone and marble are being excavated on an industrial scale. the mining has been going on for years now.

a total of 64 companies are busy blasting away the limestone hills across the kinta valley. lime is important for cement, and cement is a highly sought-after building material, in asia and worldwide. construction is a multi-billion euro business. nature pays the price. ah tat has decided to make it his job to preserve his home, the kinta valley, for as long as possible. his activists' group is called “kinta valley watch.” together, they explore the caves within the mountains and hills, which are disappearing at an ever-faster rate. ah tat's home, the kinta valley, is located on the malay peninsula in the state of perak. tin deposits were found here long ago. but limestone, granite, and marble can be excavated much more easily. ah: i want to understand what's happening here. i want to find out what's

special about these hills. in recent years, we've neglected them and all they contain. reporter: that's why ah tat is now exploring the caves under the hills. today, he's showing an archaeologist an important discovery. there are also prehistoric paintings on the limestone hills. some images are more than 10,000 years old. they are unrivalled in malaysia in terms of the nuanced picture they paint of everyday life. saw: if a quarry occurs at a site that we have never investigated before, there is a possibility that a rock art site was there and then destroyed. because from what we observed so far, rock art is distributed very widely in the kinta valley. reporter: saw chaw yeh is a researcher at usm in penang. she knows that hunters and gatherers settled early here, later switching to farming.

and its trading links to china go back to the second century a.d., as cave finds show. saw: on this survey we have discovered more than 30 rock art sites, so this is a very big leap in the archaeological research for the whole of malaysia. in the past, for like 60 years, when we were just solely based on academics and researchers, only three sites were found in kinta valley. so, because of their involvement we have got more than 30 sites now and we have a lot more to discover. reporter: but the mining companies pay little attention to the archaeological discoveries. there are 59 official excavation sites here. and everyone blasting here has a state license to do so. hills and caves where cave paintings and fossils were found are being destroyed. but none of the companies, nor the economics ministry, are willing to be interviewed on the issue. at the ministry of tourism, arts, and culture, they draw

our attention to the legal position. the deputy director is well acquainted with the regulations and is well aware that the company's profits are more important to the government. mohamad: we cannot stop the projects approved by the state. when the areas aren't expressly declared protected areas, the law dictates that we cannot stop the mining. we have no legal recourse. all we can do is to approach the mining companies and ask for talks. reporter: but these consultations are unlikely to stop the blasting in the kinta valley. ah tat is taking the archaeologist into one of the valley's biggest caves. he recently discovered a lot of cave paintings here, though he is not sure how old they are. the art in the caves is an

invaluable piece of human history. saw: rock art -- it's not only prehistoric rock art that has value, because even historical period rock art is actually evidence of the human past, human interaction with the landscape. so there's a multilayered meaning embedded within this landscape from prehistorical period to historical period. so all of these, i think, are significant to me, at least, because it shows how humans evolved through time. reporter: ah tat helps the archaeologist document the engravings and paintings. afterwards, saw chaw hey will compare the images with others. the two of them are worried that this cave, too, will disappear one day. they want to document as much as possible of the valley's cultural heritage before that happens. ah: we knew from the outset that we couldn't win.

but we are doing it anyway. and i'm not alone. i have a lot of support. i am happy because this work is an honor, because this is where i am from. reporter: there are still many caves to explore in kinta valley. for ah tat, it's a race against time. few of these invaluable finds are likely to be saved from destruction. host: sea turtles can be found in tropical and subtropical seas. as migratory creatures, they often swim thousands of kilometers in their lifetime. many species are endangered by marine pollution, fishing, and poaching. according to one study, between 1990 and 2020, more than 1.1 million animals were killed or illegally traded worldwide. but things are looking up. turtle protection efforts are on the rise -- efforts like those the people of tortuguero

on the costa rican coast have been doing for years. reporter: this is probably the most dangerous moment in the life of a sea turtle. after 60 days, the hatchlings dig themselves out of the sand and make their way to the water. this one hatched on the beach of costa rica's tortuguero national park. it's one of the animals' most important nesting sites on the caribbean coastline of central america. cloied taylor lives in tortuguero. when the turtles hatch, he patrols the beach to protect them. things used to be very different. cloied: tortuguero was an isolated place. survival didn't revolve around

money like it does today with tourism. we used to kill the turtles. we ate the eggs, we ate the meat, we ate the fins. reporter: the turtles have already travelled up to 2000 kilometers by the time they arrive at the beach to lay their eggs in the tortuguero national park. four different species of sea turtles lay their eggs on tortuguero beach, including hawksbill and leatherback turtles. gloria guerrero is a biologist with the tortuguero sea turtle conservancy. she's concerned because climate change is making the sand warmer and the higher the temperature, the fewer males are born. this poses yet another danger to the turtles' survival. gloria: out of 1000 baby turtles, only one comes back to lay its eggs on the beach.

reporter: the turtles follow the light of the moon to find their way onto the beach to lay their eggs. they only come out of the sea at night. a single female lays up to 120 eggs per clutch, spending hours digging a hole in the sand to nest in. that can take until morning. after laying her eggs, she covers them with sand to protect them from predators. she may lay up to 1000 eggs per nesting season, buried in various locations. in the first light of morning, the turtles attempt the journey back to sea. many don't make it. renato bruno, a biologist based in tortuguero, has found the remains of a turtle. it was killed and butchered for meat. renato: the turtles that nest in costa rica migrate to their feeding

grounds on the caribbean coast of nicaragua. green sea turtles are also illegally hunted on the coast there. they kill up to 15,000 turtles a year. reporter: but it's not just the animals themselves that are at risk from poaching. during the night and early morning, poachers are on the prowl for clutches of eggs. scientists keep finding nests that have been looted. keylor: this is the situation we face every night. although we monitor most of the beach, there's not enough staff to prevent this kind of thing completely. wherever we're patrolling, they just raid nests somewhere else. they poke the sand with sticks to feel for resistance, that's when they know the stick has hit some eggs at the bottom of a nest pit. once they find the eggs, they

dig them up. reporter: the turtle eggs are usually eaten raw. they're believed to be an aphrodisiac, although there's no scientific evidence. turtle eggs and turtle meat have always been an important source of nutrition on tortuguero, explains cloied taylor. cloied: the person who used to slaughter the turtles came at 5:00 a.m. then community members came with bowls and pots and asked him for some of the turtle meat. reporter: it's been forbidden to eat the animals or their eggs for more than 20 years. today, the islanders live mainly from tourism. even so, for the past 10 years, the number of sea turtles returning to tortuguero has been in decline. biologist keylor cordero is

sounding the alarm. in 2008, scientists counted 109,000 turtles nesting on the island. in 2021, there were only 44,000, a decline of more than half. keylor: there are important hunting areas in los cayos miskitos, in the caribbean areas of colombia and venezuela, where between 8000 and 12,000 turtles are hunted each year on the nicaraguan side. reporter: in some areas, eating turtle meat is part of indigenous culture. hunting is still allowed there. tourists are only allowed on the beach if they're accompanied by a local guide. they all have to wear dark clothing so that they don't disturb the turtles. we accompany the park rangers during their nightly inspection. the number of tourists per group is limited. there's a fine if the rules are ignored.

reporter: local tourism is well organized. but monitoring the area is challenging. jeffry: in tortuguero national park, 18 people are responsible for more than 50,000 hectares of marine area, more than 26,000 hectares of land, and 30 kilometers of beach front. it's just not enough. reporter: the sea turtle protection efforts still have a long way to go. but tortuguero proves that turtle hunters can become turtle conservationists, to the benefit of both nature and people. host: this week's global snack comes from venezuela. reporter: plaza venezuela is a busy meeting place in central caracas. it's a popular spot for street food vendors.

locals call this the calle del hambre, the street of the hungry. there are stalls selling all types of fast food. one typical venezuelan snack is the cachapa, a pancake made from fresh corn. cook abraham zambrano says the recipe is simple. reporter: the batter is grilled until it's crispy on the outside, then flipped. the fillings are prepared on another hotplate. customers can choose between several types of meat. abraham: our cachapas fillings include half a kilo of pork, 300 grams

of chicken, bacon, and ham. reporter: but the main ingredient is soft and gooey telita cheese. half a kilo of cheese is served with each cachapa. it's what keeps the customers coming back. >> i like the mix of the sweet with the salty, such as pork, and the cheese. reporter: a cachapa costs between $8 and $18 u.s., depending on the fillings. most customers can't finish a whole one. >> i'm stuffing my face with more than i can cope with. >> they're incredibly huge. you could feed two people with one because they're so big. reporter: this successful business is a family affair, as the chef's cousin, alavaro ruiz, explains. alavaro: we're developing. thanks to the cachapas, and my father's creation, we already have three cachapa locations, and people really like it.

reporter: venezuelans often enjoy a cachapa on sunday mornings. but there's nothing stopping them feasting on one any day of the week. and most customers leave the street of the hungry feeling very, very full indeed. global3000 is now global us for a more united world ♪ [captioning performed by the national captioning institute, which is responsible for its caption content and accuracy. visit ncicap.org]

criminal counts over the mishandling of classified documents. i court unsealed the indictment. if convicted charges carry the possibility of lengthy prison times. escape in the flood. ukrainian and russian authorities are evacuating thousands of residents in the