Designers must think carefully about their motivations for creating solar-powered products, argues solar expert Alex Nathanson in this interview as part of Dezeen's Solar Revolution series. More about Solar products are often "PR stunts" says solar designer Alex Nathanson
London-based toothbrush company Suri has created Sustainable Sonic Toothbrush, an electric toothbrush with an aluminium body and brush heads made from plant-based materials that can be recycled after use. More about Suri creates modular electric toothbrush with recyclable brush head
Promotion: technology brand HP has launched a series of large-format plotters that are energy-efficient and aimed at architects who use printers during their design process. More about HP's DesignJet plotters are "designed with both quality and sustainability in mind"
Billionaire Bill Gates has partnered with electronics company Samsung to create a prototype waterless toilet for household use that turns solid waste into ashes. More about Bill Gates and Samsung develop toilet that combusts waste "into ashes"
British company MysteryVibe has developed a sex toy that can be slipped over the penis to help the wearer achieve and maintain an erection while also stimulating their partner during intercourse. More about Tenuto 2 is a wearable vibrator designed to tackle erectile dysfunction
Promotion: Hong Kong watch brand Matte Works is launching its first product – a solar-powered timepiece called Solution-01 with an interchangeable strap. More about Matte Works launches watch informed by "sci-fi-like" solar energy plants
Australian biomaterials company Great Wrap has created a compostable bioplastic alternative to clingfilm that is made from waste potatoes. More about Great Wrap is a clingfilm alternative made from waste potato peels
Architects Frank Gehry and Sou Fujimoto are among the designers who have reimagined the iconic Louis Vuitton trunk to celebrate the fashion house founder's 200th birthday. More about Architects and designers reimagine Louis Vuitton's iconic luggage for 200 Trunks 200 Visionaries exhibition
Both sunshine and artificial light energy can be used to charge the RPT-02 SOL wireless headphones, which sportswear brand Adidas and speaker brand Zound Industries have designed for exercise enthusiasts. More about Adidas releases solar-powered headphones
Designers and academics have created a series of objects, including a bright-red wooden chair based on a medieval design, to furnish a 700-year-old castle in Northumberland, England, for the (Re)imagining Aydon exhibition. More about Modern design objects feature in exhibition informed by 13th-century English castle
Northumbria University graduate Harriet Almond has developed a prototype for a detector that can sniff out the gases released by decaying food and suggest ways to use the ingredient depending on its freshness. More about Snoot aroma detector works out freshness of food to eliminate waste
Dezeen School Shows: an interactive game designed to increase children's engagement with tennis, and a detector used to monitor head injuries from skiing are included in Dezeen's latest school show by students at Brunel University. More about Brunel University presents 10 student product design projects
An insemination dildo and an udder massager feature in the Happy Cow collection of conceptual sex toys, which Central Saint Martins graduate Ece Tan has developed for bovines based on common farming tools. More about Ece Tan designs sex toys for cows to make farming practices more pleasurable
A cup that detects drink spiking and a scrambler to block upskirting photos are among five product concepts developed by students from Brunel University to help women defend themselves from physical and sexual harassment. More about Speculative accessories designed to help women protect themselves from harassment
Subtle references to the experience of taking magic mushrooms are incorporated into the branding and packaging that Brooklyn studio Dark Igloo has designed for psilocybin dispensary PLANT. More about Dark Igloo rebrands magic mushrooms with "trustworthy" identity for PLANT dispensary
Swedish architecture and design studio Claesson Koivisto Rune has combined wool and vegetable-tanned leather to craft a cremation urn, which will naturally break down in soil once it is buried. More about Claesson Koivisto Rune designs biodegradable burial urn made from wool
Students from the Swiss design school ÉCAL have collaborated with Japanese manufacturing company Yamaha to create six devices for playing music which were showcased at Milan design week. More about Yamaha and ÉCAL students design music players that encourage physical interaction
Cutlery, candle holders and chairs were among the numerous items designed by the late Virgil Abloh that were launched at this year's Milan design week. More about Seven Virgil Abloh products unveiled at Milan design week
Swiss design and branding consultancy Brand New World has launched Hidden Sound, a flat speaker that it claims is the thinnest in the world. More about Ultra-thin Hidden Sound speakers informed by the "essentialist design ethos of Bauhaus"
Promotion: Dutch material brand SolidNature will make its Milan design week debut this month with an exhibition assembled by major architecture studio OMA. More about SolidNature to make Milan debut with OMA-designed show