T-GenX: This T-shirt generates energy and claims to be a solar alternative in certain situations

First and foremost, it’s important to note that the T-GenX is a very ambitious product from an unknown manufacturer, and it’s currently crowdfunding on Kickstarter. This means that backers will face massive financial risks and could potentially lose their money, while the technology itself could also have some pitfalls.

With that out of the way, the T-GenX is a T-shirt that's designed to generate electricity. In order to do that, it uses heat, or a temperature gradient to be more precise. While thermoelectric Peltier elements are a common and established technology, the T-GenX uses flexible modules.

According to the manufacturer, a system with 4 or 10 modules can generate 5 volts and a current of 50 to 100 or 300 to 400 mAh. This can theoretically charge smaller devices like smartwatches, headphones or even a power bank. The limitations are quite obvious, as this peak output of 2 watts is only achievable with a temperature gradient of 20 Kelvin.

With ambient temperatures well above 68 degrees Fahrenheit and especially with high humidity during summer, this is unlikely to be the case. Additionally, putting on a sweater would naturally decrease the temperature gradient and thus reduce the power output. So even in a best-case scenario, 2 watts of power would result in very slow charging.

The manufacturer more or less indirectly acknowledges this caveat by stating that the T-shirt is ideal for cold environments or caves. Whether someone would want to wear a short-sleeved T-shirt in such environments and temperatures is another question. Backers can reserve a T-GenX for a pledge of $89 plus shipping, first deliveries are expected to arrive in September. For that price, buyers can also grab a regular power bank with a small solar panel on Amazon.