around the world, people are looking to technology for clever solutions to tackle the challenges of climate change. i have come back to japan to visit some of the new world—first projects that could pave the way to a sustainable future, both here and beyond. i am tracking down the inventors turning to the sea to meet our energy needs. visiting the countryside to see robots helping an older generation of rice producers. and vertical farming taken to a whole new level. i want to eat this! this is tecthlore japan. it's known for its megacities, butjapan is, above all, an island nation. hemmed in by the ocean on all sides, land is at a premium. that means when it comes to green energy, there is less room for the cheapest power source of all — solar. actually, the biggest change we are seeing right now is the rapidly decreasing costs for solar. it would be more expensive to operate fossil fuels than solar in the near future. as i start my sustainable tech journey throuthapan, i am headed to the islands of tokyo bay. this is the site of japan's first—ever offshore solar farm. olaf, hi! nice to meet you! nice to meet you, too. here we will put our offshore floating solar platform. solarduck is the company behind the build. it's part of a group of start—ups coming up with sustainable designs for future urban life. so, that's the site down there? yeah, basically this is a c6! of the project here in the tokyo bay. the solar array is designed to be modular. each unit can power a0 households a year. more can be added to meet demand. it can survive anything at the ocean can throw at it. the triangle has three xs where it can rotate around. if there are waves from any direction, it's easily able to follow, and this make sure that we can actually also survive very high waves. it is a hugely impressive concept, but even cleverer than the design of the solar farm is how the green energy it produces could be carried back to shore. nearby, another start—up is working on this side of the project. this little boat is the key and what i am here to see. hi! hi, how are you doing? good, hi, nice to meet you. good to meet you too. wow, this is beautiful, isn't it? yeah, it's a wonderful day, thank you for coming out. check this out. let's go jump on a boat. the team is developing this vessel to collect small loads of renewable energy generated at sea. it's trying to get away. there she blows, she's away! everblue�*s boats use wind power to sail all on their own with sensors navigating the course. they have on—board batteries, which will be charged by the solar farm. the power is gathered and can be transported by boat. the aim is these boats will operate in fleets, creating an affordable alternative to undersea cables. the cable has to be so big and it is really expensive. so, what we do is take these boats to a place where, let's say, we have a floating solar panel array or floating wind. it's a very common thing. and we can take the energy from those locations and transport it to where it is needed. if this succeeds, its scale could be game changing. a completely different way of approaching energy transfer. at a time where the world must adopt green energy at pace. because the boats are wind powered, no energy is needed for theirjourney, meaning the whole process is much more sustainable. we are not using the energy to transport our energy, so it is a lossless system and so we can transport a kilometre, ten kilometres, 1000 kilometres, it does not matter. it is hoped these boats could help bring green power to over 4 million people living on hundreds of islands across japan. the boats could also serve future floating projects like this one. floating islands, these things could be mobile. imagine these guys are workerhands and they're transporting constantly to the mothership. it has been fascinating to see how a technology as old as time, a simple sail, has been repurposed to deliver a sustainable energy solution. it will be really interesting to see how it develops in years to come. a year ago, i visited choshi on the other side of tokyo to see japan's first bottom—fixed offshore wind turbine. the noise is really something else. it quite intimidating being this close to it. as i found out, the bigger blades commonly seen at sea and on land have drawbacks. most wind turbines stop working at around 90 kilometres per hour. anything more puts their blades at risk of damage. across asia, high wind typhoons are becoming ever more common. i'm visiting a start—up that has made a new type of turbine, and surprisingly there is not a single propeller blade in a site. this is itjust here? yes, this is our turbine. this is on one tokyo's urban evacuation sites where locals gather in emergencies. its vertical access can catch wind from any direction and it's practically silent. everyone can charge their phone. that is good, i am low onjuice, so let's give it a go. it is charging. it is! this is just a small prototype. a biger ten—kilowatts version is on another island. it can operate in higher winds, and, crucially, its propeller—free design makes it much more resilient to typhoons. it is not that windy today and it is still turning pretty fast. when the winds do stop these working, solar panels continue to generate energy. local communities often have a bit of pushback against renewable energy because it is noisy, it takes up too much space, but if you have projects like these which can be erected in urban places, i think this would be really important to push the renewable acceleration forward. japan is getting used to ever stronger typhoons, but when it comes to showing resilience, few places come close to my next destination. fukushima. japan's biggest ever earthquake in 201! caused a tsunami and the fukushima daiichi nuclear plant went into meltdown. the devastation displaced over 150,000 people and many never returned. i am heading to the north of the region, to soma, a place rebuilt to entice populations back to the area with unrivalled green credentials. this soma project serves as a testbed of ideas which could be rolled out across japan and around the world. everything here is connected. the solar farm collects the sun's energy. it produces 1.6 megawatts of electricity. 0n sunny days, it produces more energy than the neighbourhood needs. usually it is during the battery storage process a lot of this power is lost. this facility looks quite simple but this is where the surplus energy is converted into hydrogen. hydrogen is a very efficient way of storing energy because very little is wasted. it does that through electrolysis, which is splitting hydrogen and oxygen out of water. yes. beyond the energy efficiency, hydrogen is being used to test lots of cutting—edge ideas. some is combined with c02 captured from the atmosphere to create eco—friendly fuel for locals. this is the e—methane dispenser. to fuel the small mini band for elderly people to move around to the soma city.. the first e—methane dispenser injapan. wow, look at that. these fish ponds are aerated with oxygen left from the hydrogen processes. wow, i can see them, they are massive. here he comes, look at him! dinner time for the fishes. yes. the lettuce gets nutrients from the fish and they thrive on carbon dioxide that has been captured and pumped in from outside. i don't have green fingers, but they look pretty healthy to me. the local farms use fertiliser made from repurposed sewage. we palletise the waste. rather than having to track the waste around the country, you use it here to grow things and save energy? exactly. smart. sooma is one of the most sustainable projects i have ever seen. the ideas here are being driven by this man. everything here is designed to make soma more sustainable. a fresh look at bringing green energy into the community. if an earthquake were to strike again, the hydrogen will power vital services in soma. something we tested in a simulated power cut. the lights come on! yeah, almost immediately. the gas is piped off to be converted to electricity. wow, i can hear that. and off site to the disaster relief centre. it all happens automatically and that means that people can still get electricity even when everything else has gone down? yes, you are right. that's very cool. it needed something big, something to say that soma is the future, that it is a place where people can come and live. boy, have they delivered. sustainable energy solutions will be vital across the world. japan has another concern — maintaining sustainable communities. i am travelling 250 kilometres north of tokyo to a small town in nagano that is at risk of disappearing. nagano translates into english as "a long field", and considering how lush and green it looks outside, that seems pretty fitting. rice, so synonymous with japanese cuisine, has grown here for over 2000 years but those who farm it are struggling to keep up. more than half of the residents here are over 60, as farming falls out of favour and youngsters are lured by the lifestyle of japan's cities, there are fewer people able to attend to this vital crop. i am meeting a woman from a start—up supporting farms as the labour force shrinks. hello, how are you? very good, lovely to meet you. wow, this is a rice field? yes. it is beautiful. it is a lot hillier than i was expecting. yes. raised dams keep the water in each field but it means significant weeding for farmers, who must patrol the paths to spread fertiliser and deter pests. farmers like this. for ageing farmers, it is robots to the rescue, as this smart phone mower keeps weeds in check. just press here, and then push pilot. just press that and off it goes? amazing! how does the robot know where to go first, human has to tell them and then a robot can run independently by using sensors. facing many more hazards and tougher terrain than your average lawnmower, data from satellite systems, direction, geomagnetic thermal sensors keep the robot on track so just one pilot can monitor several mowers at a time. central power can see the map here. i can see where it is in the field right now. this prototype uses petrol but is due in electric upgrade next year as a team works to bring a subscription service to farmers like this one, his been testing the robot since 2019. supporting farmers is not enough to save this area on its own. just down the road is the nomad work centre, the hub where tech pioneers can create projects from the seat of nature. the neighbouring campsite attracts eco— friendly tourism but they need staff to man it round—the—clock. are there hikes nearby? so the team is training a it help visitors when real—life humans cannot. i have questions about the campground. are bonfires allowed on the campsite? 0pen fires are not allowed, please use a fire pit or barbecue. good advic! wow! this space is beautiful! i can absolutely see the appeal of coming to spaces like this to work or explore and what a view for dinner! not only can robots help ageing farmers put locally sourced food on the table, but sites like this are boosting interest and reinvigorating the local community. it is inspiring to witness efforts to preserve this area and its iconic rice patties. climate change is making traditionalfarming more difficult the world over. i have seen vertical farming with its bright purple lights injapan before but the next project i am visiting is on a whole other level! and i am one of its first outside visitors. hello! the most extreme steps are required even to enter. all of this to ensure the facility is kept hygienically sealed. i'm going into an airlock, what will happen next? wow! this is an experience! what is waiting for me is breathtaking. wow! it is absolutely huge! incredible! it is like being in a farm in outer space and like outer space, very few humans can come here. this is like no farm i have ever seen. all of the growing is happening behind these sealed units, a completely closed system. this is our system. there is so much growing here. what is the advantages of growing like this? because the closed system can control the inside very precisely, the temperature, humidity and the c02 concentration, there are 20 parameters. in allowing such microcontrol, this closed system is already proving greener. an open system waste half of the light on lead. that is quite a lot! a 30 metre long robotic system sits at the heart of all of this. where 150,000 lettuces are being grown forjapan�*s biggest supermarket group. here comes some freshly grown lettuce. truly automatic. what are the benefits of doing it all automatically rather than having people do this work? the machine operation is totally clean so we do not need to wash the vegetables before eating. we can save resources such as water, which is good for the planet. this lettuce saves 12 litres per water? per head. per head of lettuce? that is a lot of water! in the start—up�*s lab, i am shown other greens, like basil. you can smell it. you really can. it smells amazing! it is making me hungry! but not everything is for eating. because of the position, plants medicinal use can be grown more easily. i can see the flowers. they are very small at the minute. look at them. these are being grown for painkillers. others, for cancer research. the system is so precise, the most difficult plants to grow can be sourced at speed. how does that feel helping to research plants that may one day cure illnesses like cancer? and without humans sharing the environment, oxygen levels can be dropped in temperatures pushed to extremes, whatever is necessary to perfect each ingredient. what is happening here really is incredible. and as we all live longer, it is another example of japan's innovators helping us all live better. how to live sustainability is the question the whole world is trying to answer. whether it is finding new energy solutions or thinking differently about how we live and age together, japan is working on ideas that can inspire us all. perfect! hello there. today has been a little bit quieter compared to yesterday afternoon and through the overnight period where we saw substantial amounts of snow spread across parts of england and wales, leading to some disruption. the rest of this afternoon, it does stay cold, maybe not quite as cold as the last few days for england and wales. and we'll see further rain moving up from the south with some sleetiness over the higher ground. so that rain coming and going for the rest of the afternoon through the evening. but we'll start to see some more substantial heavy rain pushing up from the south as we move through tonight. and as that bumps into the colder air lying across the northern half of the uk, we'll start to see some snow with the higher ground of wales into northern england. so less cold across southern areas through tonight, but another cold one to come with the widespread frost and some ice to watch out for across scotland, far north of england, northern ireland. now for the monday morning commute, we could see some tricky conditions with this rain likely to see some snow over the high ground of the welsh hills, the peak district, the pennines, even some wet snow down to lower levels. so just watch out for that could cause some disruption for most though across england and wales, it's going to be a cloudy morning and afternoon with outbreaks of rain coming and going. that rain pushing its way northwards. wintry showers feeding into eastern scotland. these could give some accumulations at times. but the best of the sunshine, western scotland, parts of northern ireland, just the odd shower here and then quite breezy, feeling chilly. even though the temperature is a little bit higher, you factor in the wind, it will feel pretty cold and raw wherever you are. that area of low pressure starts to pull out into the near continent during monday night. so for tuesday, it's more eastern parts of the country affected by this low pressure system with north, north—easterly winds, which will be quite a feature, making it feel really cold down the east coast of england. a few wintry showers. a few wintry showers in northern eastern scotland. 0therwise, further north and west that you are under a ridge of high pressure, the calmer it will be. blue skies, some sunshine and the winds a little bit lighter. but it will be a chilly day wherever you are on tuesday, 2 to 7 degrees, feeling better in the west with some sunshine. wednesday, another cold day to come. a quiet day, but then notice beyond wednesday, thursday, friday, it's looking much milder, but low pressure taking charge. so it will be unsettled. so we do start the new week off on a cold note. by midweek it starts to turn milder. but with that comes the wet and windy weather at times. live from london. this is bbc news. with no let up in israel's intensified bombing campaign in southern gaza, hamas officials say hundreds of palestinians have been killed in 2a hours. the us defence secretary warns israel it risks driving civilians into the arms of the enemy. glenys kinnock, the former british minister and wife of the former labour leader neil kinnock, dies, aged 79. a german tourist has been killed and two people injured — including a british man — in a knife and hammer attack in central paris. heavy snow causes major disruption in england's north. police urge people to stay away. hello i'm maryam moshiri. we begin with the latest developments on the israel—gaza war. my colleague anna foster is injerusalem. intensifies its many operations on the south