We featured a bulky motorcycle air-conditioning unit in February 2014 that sat on the back of the bike, but this latest invention is much lighter, smaller and hangs off your trousers to pump cold or hot air into your jacket. It’s called MiClimate and the makers promise it will hit the market at about US$269 with battery, having easily reached its crowd-funding goal of $20,000. The invention comes from a company based in Phoenix, Arizona, which is in the desert and experiences extreme climate changes from around 100 degrees (37°C) maximum in summer and 50°F (10°C) in winter. It is based on a Personal Wearable Climate unit used by the US Navy in 2009. While there have been other attempts at motorcycle air-conditioning in the past, this is portable because it uses electronics, rather than a bulky compressor. It’s about the size of a big hard-bound Harry Potter novel, weighs 1.5lb (0.68kg) and fits around your waist via a belt. You can power it with a rechargeable 12V lithium-ion battery that will last about four hours, or connect it to your bike’s battery which saves you $20 on purchase price. It is controlled by a Bluetooth remote that attaches to your handlebars, or you can press buttons on the control unit to increase or decrease air temperature which blows inside your jacket. MiClimate may still be a bit bulky, but it could mean you don’t have to go without a jacket and safety to stay cool in extreme heat.See alsoBike accessoriesGear/accessoriesiPhone 13 accessories coming soon The manufacturers claim it will reduce ambient temperature by 18°F (10°C) or increase it by 36°F (20°C). The effect may depend on your jacket’s fit and whether you have vents for the air to escape. Without having tried it, we think it could deliver cool/warm air where it enters the jacket, but you could still be hot/cold at the other end of your jacket, creating an uncomfortable imbalance. But at least it shows a willingness to battle the problem of temperature which can have an effect on the concentration level – and therefore safety – of a rider.