this is bbc news. the headlines: joe biden has accused russian president vladimir putin of being a �*butcher�* in his treatment of ukrainians, saying he �*cannot remain in power�*. the us president was speaking in poland where he met ukrainian refugees. the white house said mr biden had not meant he was supporting regime change in russia. the western ukrainian city of lviv has come under heavy rocket fire. the regional governor said five missile strikes hit a fuel depot and an industrial plant. lviv�*s mayor said no one was killed but five people were injured. and there have been tributes for taylor hawkins — the drummer with the rock band, the foo fighters — who's died at the age of 50.

officials in colombia say he used opiods, marijuana and anti—depressants before he died. his body was found in a hotel room in the capital, bogota. now on bbc news, click.

solar power is the earth's most abundant energy source. and today that goes far beyond simply plonking panels on rooftops. we keep seeing scientists develop new ways to make the technology more flexible, more powerful, and more useful. this factory in stockholm is making ultra—thin solar cells that don't even need sunlight to harvest energy. the idea is they can be used outside or inside your home to power products. i will be showing you later on what that means for various devices. but first, here's dan simmons who's been looking at how solar could help the energy price crisis. although most of us like the idea of clean

energy, so far we've not been persuaded. maybe it's because we don't own our own roof. or it's the upfront costs. maybe we are thinking of moving and feel we can't take solar panels with us. or just those glaring large slabs isn't quite the look we're after. so i've been to the homes of two british start—ups. who want you to look again. this is the solivas arc. it's curves are wrapped in an organic solar film which doesn't contain any toxic substances nor rare earth materials that could require mining. and so it has a much smaller carbon footprint than traditional panels. and that's not all. now the arc is designed to capture sunlight throughout more of the day. and that is partly because it's got five surfaces on which to harvest energy.

and this curved design means that usually it has a sweet spot which is very useful at the start and end of the day in particular. i think it looks quite futuristic. and if solar sculptures like this were to catch on, i can see them being seen as a sort of carbon neutral status symbol. something for the neighbours, perhaps to gawk at. i don't like the look of conventional solar panels. ijust don't like them. so i thought well, i want to get the home energy independent but how can i do it with avoiding solar panels? so started looking into new solar technology that was out there. this is solivus�* testing yard in kent where they've been adapting the shape of the sculpture to maximise efficiency. the multilayered solar film used is provided by german firm helio tech. these solar panels are made up of three distinct layers

at the moment and the top layer will capture the high energy light. the middle layer will capture the sort of visible light and then the bottom layer captures more of the infrared, more of the heat. so maximum efficiency for conventional solar panel is about 33% whereas for this technology they can layer it with in theory as many layers as they want to choose different parts of the spectrum and capture overall more light coming in. despite this sunny outlook, today this solar film is only 8% efficient. with a 10% version expected later this year. last year that may have been a problem, high initial costs have dogged solar as a cost—effective option. until the maths changed. driven by supply issues and fresh demand from a world recovering from a global pandemic, energy prices are surging. more than 50% in a matter of minutes. and that was before many western nations imposed sanctions on russia's gas and oilfollowing its invasion of ukraine.

with the uk's energy price cap lifting next week, many household bills are to soar. from around 18p per kilowatt hour last year, the variable rate of electricity is expected to jump to more than 26p by the autumn and at least 32p if you want to fix your prices for a year or more, depending on where you live in the uk. at £3,500 the arc isn't cheap. but it is guaranteed for 20 years. it's film panels which are upgradable are expected to produce an average of 1000 kilowatt hours per year by the end of 2022. when it becomes thousand kilowatt—hours a year, in the uk you are looking at about 21p per kilowatt hour.

that amount of energy will be locked in at that 2ip for 20 years and after that, it's free, obviously. let's be clear, one of these isn't enough to power the home. even one that uses gas or oil for heating. in theory you would need at least one for every bedroom you have. and if you don't have an expensive battery to store any surplus energy as it is captured, you end up feeding it back to the grid for a fraction of the market price. one alternative is you can plug the arc directly into your electric car if you have one. i found another solo entrepreneur in london's notting hill. this prototype features a unique cost—effective way to attach solar film to regular blinds so owners of flats and garages can take advantage too. because to date solar power has been for the rich, and it has not been, there has not been a system or product in place where it can go on any building. my company's aim is all around the democratisation of solar so any window can now become

a solar panel. david has applied for a patent for his creation and will take it first to spain where these types of blinds are more common. installations begin later this year. and he is also in talks with a london authority which wants to fit them to council flats. so for this size of window it would generate around 10%, 15% of your energy needs, and this is a three bedroom house. so between a hot summer or a cool winter, the amount of energy you could generate would be probably about ten, 15% less during winter compared to summer. so not much difference? not that much, no. and with this new solar film it generates energy in cloudier climates compared to silicon panels. another good thing about solar film is that it is scalable. some places have more roof space than of course.

so for reasons of cost savings as well as the environment, this rugby stadium has decided now is the time to cover its stands in a new, lightweight solar film. there is an estimated 2.5 billion square metres of south facing commercial roof space in the uk. and a lot of it wouldn't have enough strength to support weighty, traditional solar panels. so the panels will pay 15p per kilowatt hour. that is half or less than half of what the current cost of electricity is so that is a significant saving for us. if you've got a big roof or big area of land, i don't know why you wouldn't consider this as a viable option. i mean, you know, it uses an asset you cannot really use for any other purpose. it saves you money. and it's good for the planet.

increasingly these new types of flexible solar panels are making solar more accessible for people. the don't replace traditional panels, which will be ideal for some. and there are other options like solar tiles out there too. but solarfilm is now getting more efficient and importantly, cheaper. just as grid prices are going through the roof. so both practically and financially now, solar could be coming home. here is a way of making your gadgets greener by using sustainable energy. something this solar cell factor in sweden is taking to the next level. this machine is printing custom nano ink onto solar panels and they don't even need the sun to charge. it was the week sony unveiled the designs of the playstation 5

virtual reality headset. microsoft said a single employee's account was compromised but no customer code was compromised and finally the electric truck has completed its testing programme driving one step closer to serious production at the end of the year. engineers focused on how the track performs under harsh conditions. not rush—hour traffic. instead, temperatures low as —30. it is coldly going where no truck has gone before. we know that fashion can hurt the earth. its production makes

up the earth. its production makes up 10% of humanity's carbon emission, dries up water sources and pollutes rivers and streams. but all products, whether they come from farm slabs of factories take their toll with hidden impacts on materials, manufacturing and more. frankly, it can be really hard to know which items that you want to buy a better for the planet. take these two shirts. they look pretty similar on this one might be made for more sustainable materials but if it has been flown halfway around the to get you where is this one has been made locally how one you know which one to choose. wouldn't it be nice if you could scan the products to see what is good and what is bad? here one company is trying to make the environmental impact of products more transparent. the idea she's done the code and you get a score out of 100. this is 66. this motion is that

pretty much the same, 70 out of 100. ok. slightly better. oh how that one. the co—founder explained that this score actually consists of five sub—scorers assessing things like carbon emissions, materials and recyclability and the impact on the people creating it. 68 for lavender melts. how necessary a product thatis melts. how necessary a product that is also gets a score. what is an example of a product with no purpose? they can electric peppe" no purpose? they can electric pepper grinder. 500 fashion home and beauty brands have been signed up in the system binds itself to a major bingo scores can be easily displayed next to the products. the idea is that anything and everything

could eventually have their standardised label. there is already an industry standard for working out environmental impact. it is called a bicycle assessment but this requires brands to dig deep into their data, a lengthy and expensive process that few companies bother to do. no brand has all the information that we need so you have certain areas of sourcing or distribution, we call upon 31 different databases. eventually they will have one big database of the environmental impact all parts of the production process with al being used to estimate any ai being used to estimate any unknowns in this open calculation timestamp months to weeks. if you come in the t—shirt and say it is made of organic cotton produced in sri lanka and we knew where it was produced a new word went to to

be manufactured and then to be sold that is enough for us. is that guesswork here because if you don't know exactly how it got me to be could be a great way are not great way. you make it builds on itself. we have scored tens of thousands of products. if we don't have the information that we have enough databases to get the accurate score. it says it can produce results that are 80% accurate and could devise a score without any information or even consent from brands could be years away. a breakdown could even help the worst offenders to improve. it is high—impact. you can different materials or

areas. by plane, track and ship. you can try to do that a different way. write about what you're doing is clever because instead ofjust you're doing is clever because instead of just effectively possibly naming and shaming brands which don't do very well you're providing them with thoughts of information. we try to show the brands the things that they can do. white make the would be apprenticed to display all five of its cause rather than just picking on the highways their strengths but opinion on what is most important will vary between customers and the science behind this course will evolve to. many might mean that product score changes as sentiment shifts. one benefit is brands compete with each other to get better scores. that is the aim, obviously.

that is the aim, obviously. that healthy competition that we want. , ., ., we want. there you go. in the future you _ we want. there you go. in the future you can _ we want. there you go. in the future you can know— we want. there you go. in the future you can know exactly . we want. there you go. in the i future you can know exactly how green your entire outfit was. i don't have to wear green, devoy? what make you keep in the blue and i will rock the grey. he was a way of making your gadgets greener. by using sustainable energy. something the solar cell factory in sweden is taking to the next level. this machine is printing custom nano ink onto solar panels and they don't even need the sun to charge. seo make in this machine the printer ink. how is the usage of it different to other solar cells? it is like photosynthesis. they can work_ it is like photosynthesis. they can work in a right condition.

any— can work in a right condition. any kind _ can work in a right condition. any kind of— can work in a right condition. any kind of light. it is electricity used anywhere. we are recycling right. the extra efficiency— are recycling right. the extra efficiency means that those silver — efficiency means that those silver strips that usually run through— silver strips that usually run through solar panels are no longer— through solar panels are no longer needed. freeing new design — longer needed. freeing new design ideas. this allows us to have _ design ideas. this allows us to have printing so we can print a solar_ have printing so we can print a solar cell— have printing so we can print a solar cell for you in the shape of a _ solar cell for you in the shape of a circle _ solar cell for you in the shape of a circle or triangle. any device _ of a circle or triangle. any device. , . , , ., , device. cells have been shaped to fit a headphone _ device. cells have been shaped to fit a headphone band - device. cells have been shaped to fit a headphone band and . to fit a headphone band and this robot is responsible for squirting electrolytes onto them to allow conduction. it looks like it will grip bits in between. it looks like it will grip bits in between-— looks like it will grip bits in between. ., , �* ., , between. it doesn't make any mistakes- _ between. it doesn't make any mistakes. the _ between. it doesn't make any mistakes. the final _ between. it doesn't make any mistakes. the final step - between. it doesn't make any mistakes. the final step is - mistakes. the final step is lamination _ mistakes. the final step is lamination to _ mistakes. the final step is lamination to give - mistakes. the final step is lamination to give the - mistakes. the final step is| lamination to give the cells custom textures. he was the

finished product. a 1.3 millimetres thick solar cell. tell me about the prototypes. you see sustainable poet headphone. it will absorb any kind of light and converted into energy. go to your office, take a walk may sit in the office working. we go to the gym, whatever you do, it will always charge during the day. the luxury of not needing conventional charging will add a chunky $50 to devices. several of which have already been created. this is a self powered speaker. if you live, but here it is a solar cell. a smart helmet can sense when it is worn in the dark and light up is worn in the dark and light up automatically. here are the charging panels one, two and three. and this bag doubles up

as a power bank. this is a big surface and you can place it in charge a lot. charging from ambient light does have limitations, though. how about a laptop? how far away you from being able to create that power in the bag? it is super power hungary. on the phone as well, you won't get enough. laptops and phones need much stronger light or you need a larger surface. it is all about finding the balance, right. the coman finding the balance, right. the company thinks _ finding the balance, right. the company thinks that an apple help users develop better charging habits by making everyone more light conscious, as they put it. everyone more light conscious, as they put it— as they put it. the largest oint as they put it. the largest point globally. _ as they put it. the largest point globally. they - as they put it. the largest point globally. they no i as they put it. the largest - point globally. they no phone how much it charges and drains all the time. you can track how

you are doing. i am told this tech will never be put directly on smartphones because, well, leaving your smartphone in the sunshine is never a great idea, but this could a step up from wireless charging for many other devices. products like these headphones do still have a back—up charging port. these headphones do still have a back-up charging port.- a back-up charging port. lover was heping _ a back-up charging port. lover was heping to _ a back-up charging port. lover was hoping to power— a back-up charging port. lover was hoping to power up - a back-up charging port. lover was hoping to power up with l a back-up charging port. lover was hoping to power up with a | was hoping to power up with a bit of sunshine. talking of which, it was the summer sunlight which gives the visual effects team a bit of a headache. their brief was to recreate a harsh desert planet full of sand worms and flying ships all the while making it look realistic and grounded. he was a look at the amazing work that went into the film.

i knew they were going to try and grounded in reality as much as possible within a science fiction movie but try and have it in a way and where it was as if you are filming as if it was real. so not visual effects for visual effects sake but to tell the story. move the story along. and that is type of work i quite enjoy doing so neither would be a lot of preservation needed. sand dunes shot with a real camera. we would then need to match that completely digitally to be able to put sand worm in this example, sand worm to the genes. i knew it would be as photorealistic as we could get it. it would be as photorealistic as we could get it.— we could get it. it started on day one- _ we could get it. it started on day one. sand. _ we could get it. it started on day one. sand. sand - we could get it. it started on day one. sand. sand in - we could get it. it started on day one. sand. sand in the l

we could get it. it started on - day one. sand. sand in the worm and how do we make this happen and how do we make this happen and make it look 100% 30 real and make it look 100% 30 real and yet be able to see different versions and men do attend, you know, have it still therefore that camino, i map shows? ., , , shows? one of the biggest challenges _ shows? one of the biggest challenges was _ shows? one of the biggest challenges was the - shows? one of the biggest challenges was the issue i shows? one of the biggest| challenges was the issue of scale — challenges was the issue of scale in _ challenges was the issue of scale. in the deserts there is no vegetation so we did not have — no vegetation so we did not have that is a skill reference for the — have that is a skill reference for the eye to look at. which is good _ for the eye to look at. which is good and bad. it meant that we had — is good and bad. it meant that we had to— is good and bad. it meant that we had to have almost a full simulation of the different grains _ simulation of the different grains of sand in there to make that work— grains of sand in there to make that work so early tests were 'ust that work so early tests were just too — that work so early tests were just too big. so the effects team — just too big. so the effects team had to come up with different ways of working with that — different ways of working with that. obviously you cannot

simulate every single grain of sand — simulate every single grain of sand in— simulate every single grain of sand in the desert. that is not possible _ sand in the desert. that is not possible. they came up with systems _ possible. they came up with systems where you could have a representation of it is likely to look— representation of it is likely to look like and they had systems in iran from a library of different setups that they have — of different setups that they have two then populate some of the areas — have two then populate some of the areas around to get that feeling _ the areas around to get that feeling of this desert. from the simulations we had dust which — the simulations we had dust which dealt with the scale, tou — which dealt with the scale, tou and _ which dealt with the scale, too. and shifting sands. some of the — too. and shifting sands. some of the dues of that bit further out from _ of the dues of that bit further out from the worm is. it is sending _ out from the worm is. it is sending out vibrations and shifting _ sending out vibrations and shifting sands left and right in frout— shifting sands left and right in front of it as it moves forward _ in front of it as it moves forward-— in front of it as it moves forward. . , ., , , forward. we built partial sets and so we — forward. we built partial sets and so we had _ forward. we built partial sets and so we had real— forward. we built partial sets and so we had real ones - forward. we built partial sets and so we had real ones on l forward. we built partial sets l and so we had real ones on the set and helicopters landing to kick off the dust so we could use that is referenced to replicate. there is a lot of virulent sweat and tears in that movie. it was a very

special project that everybody wanted to be there and do their best and you see that on the screen, a lot of that love is “p screen, a lot of that love is up there. screen, a lot of that love is up there-— screen, a lot of that love is u- there. , , , , up there. the test is simple. remove your _ up there. the test is simple. remove your hand _ up there. the test is simple. remove your hand from - up there. the test is simple. remove your hand from the | up there. the test is simple. - remove your hand from the box. and you die. remove your hand from the box. and you die-— and you die. what is in the box? pain. _ and you die. what is in the box? pain. that _ and you die. what is in the box? pain. that is - and you die. what is in the box? pain. that is it - and you die. what is in the box? pain. that is it for - and you die. what is in the | box? pain. that is it for this beat. box? pain. that is it for this heat you — box? pain. that is it for this beat. you can _ box? pain. that is it for this beat. you can keep - box? pain. that is it for this beat. you can keep up - box? pain. that is it for this beat. you can keep up with | box? pain. that is it for this i beat. you can keep up with the team on social media. find us youtube, instagram, facebook and twitter. thank you for watching. goodbye.

hello, there. well, for most of us, saturday brought much in the way of sunshine. top temperature, 20.5 celsius was recorded in north west wales in porthmadog. i want you to concentrate, though, on the skies in eastern england, where we had lots of sunshine and temperatures quite widely17—19 degrees. big change on the way, though, for sunday afternoon, as those temperatures are going to be a lot lower. now, the reason for that, is we are going to see an area of cloud that at the moment is in the north sea and that is set to swing inland as the winds of change direction to more of an easterly around our area of high pressure. now, there really will be just two types of weather around on sunday. it is going to be a cold start for many of us, a few patches of frost around. you're either in the sunshine, which many of us will have, or this zone of thick low cloud, which could bring a few spots of morning drizzle, be a bit misty as well. perhaps tending to brighten up a little bit into the afternoon across parts of the south—east, but a slow process and there could be areas where the cloud lingers all day. lincolnshire, norfolk, most prone, temperatures there could just get to around eight or nine, still in the best of the sunshine,

it will be another warm day for most, with temperatures again reaching the high teens. there will be more of that dry weather, more sunshine to go around on monday as well, but, across the far north of scotland, in shetland, we are going to start to see the winds turn to a more northerly direction and some colder air will be edging in here. still, weather wise for most parts of the uk, we are looking up fine, blue skies and much more in the way of sunshine. still mild for the time of year, but into the middle part of the week, we get these much colder northerly winds diving their way southwards, they are going to absolutely hammer the temperatures. that changeover really starting to take place on tuesday. there will be quite a bit of cloud around, a number of showers and that colder air starting to make further inroads across northern scotland. just six or seven for aberdeen and stornoway, still quite warm with temperatures into the high teens across parts of wales and south west england. now, for wednesday, there will be some further showers around, temperatures continue to drop away and some of the showers turn wintry of the higher ground and then, look at this, wednesday night, into thursday, into friday morning, which is april fools' day,

could see a spell of hill snow across the pennines and wales and maybe down to lower levels. we will be keeping a close eye on developments over the next few days.

this is bbc world news i'm rich preston. our top stories: president biden meets ukrainian refugees in poland, before delivering a stark warning to russia's vladimir putin. don't even think about moving on one single inch of nato territory. as the president prepared to speak, russian missiles hit a fuel depot in lviv, close to the polish border. as fears grow of hidden spies and saboteurs within ukraine itself, we have a special report from the city of odessa. and tributes from across the music industry for taylor hawkins, the drummer with the rock band the foo fighters, who's died at the age of 50.