Launch HN: Voltair (YC W26) – Drone and charging network for power utilities

Here’s some footage: https://vimeo.com/1173862237/ac28095cc6?share=copy&fl=sv&fe=... and a photo of our latest prototype: https://imgur.com/a/bYHnqZ4.

The U.S. has 7M miles of power lines (enough to go to the moon and back 14 times), and they're aging. Over 50% of all power flows through transformers that are at least 30 years old, which is about when they start to fail.

Power line conductors are just bare metal with 4,000-765,000 volts sitting on ceramic insulators, usually held up by pieces of wood. It’s a cost effective and relatively reliable way to move power. But when the wood starts to rot, or the cotter pin falls out, and a live conductor is dropped on a dead tree on a windy day, you get devastating wildfires like the Palisades Fire in LA last year.

Most utilities solve this problem with foot patrols. Linemen drive out with a clipboard or an iPad, and run through a checklist with binoculars to visually confirm everything is in order. A lineman can inspect about 50-150 poles per day, yet even the smallest rural electric cooperatives (with about ~20 employees) have about 50,000 distribution poles. Clearly the math doesn’t work out. As a result, a given utility pole is inspected about every 10 years (at least that’s what they tell their insurance adjuster).

Helicopters are also used, but cost $25k to get off the ground, and more importantly, every year linemen die in helicopter crashes. Satellites can’t deliver the mm precision needed for these inspections. So drones have emerged as the best solution. Georgia Power saved 60% on operating expenses when they switched to using drones, and Xcel power found drones to find 60% more defects than foot patrols (because of pole-top vantage point).

Problem #2: Drones are held back by the need to constantly recharge and FAA beyond-visual-line-of-sight (BVLOS) regulations. In response, the most well funded utilities (e.g., PG&E, SCE) primarily send out pilots in trucks to collect the data.

Current leaders in the drone space – Skydio and DJI – have built drone-in-a-box solutions. Their charging stations have inherent concurrency constraints (only one drone at a time) and don’t scale easily over large land areas. Skydio charges $250,000 / box, and has a there-and-back range of about 15 miles (assuming ideal performance). They are expensive and inflexible.

Our first solution (and why it didn’t work): We entered YC wanting to build drones that charge inductively from the magnetic fields around power lines. We used a split-core current transformer, wrapped it around the conductor with a clamp, and harvested power. We spent about 4 months testing and developing this hardware, and successfully recharged a few batteries in the field. It was a really cool proof of concept.

But we ran into a big problem. There’s not enough current on distribution lines! These are the wooden poles outside your home, as opposed to the tall steel transmission towers you might see in the countryside. Generally speaking, we needed about a MW of power – or about 1000 homes – to flow through the lines to charge our drone performantly.

We also found the risk-reward calculus didn’t make sense for utilities. Line attachments (and even inductive power harvesting) is common in the utility space. Fault indicators and smart sensors like the Heimdall Power “Neuron” do this. But they are installed one time with lineman supervision and left in place for years. The risk of landing a drone multiple times per day at myriad points around the network felt too risky for utility engi...