If your home Wi-Fi router wasn't cooped up indoors, it could send a signal about a 20th of a mile before the signal became too weak and distorted for a computer to receive it. Technology developed by San Diego startup On-Ramp Wireless uses the same frequency, but less power, to send data signals 45 miles, thanks to algorithms that make the signals very resistant to noise.
 
The technology, called Ultra-Link Processing, transfers data at a very low rate compared with a home broadband connection. But On-Ramp intends to offer it as a way to enable "smart energy" grids, in which simple sensors installed in home energy meters, for example, report local activity back to utilities, allowing them to manage power generation and distribution more intelligently.

Smart-grid infrastructure is needed to cope with the fluctuating output of renewable energy sources at large scale, and it could make feasible micro-generation, whereby consumers make their own power and sell any surplus back to the grid. Today's smart-grid sensors typically use Wi-Fi-like technology with Wi-Fi-like ranges, or unlicensed radio bands that can reach a couple of miles. Cellular networks can also be used, but these connections are under growing pressure from data-hungry phones and tablets.

"There's no technology available for devices that just need a trickle of connectivity over long distance," says On-Ramp's chief technology officer, Ted Myers, who says that with a clear line of sight, On-Ramp's technology can send a signal 45 miles. He is targeting devices that use less than 50 bits per second, roughly 100,000 times less than the average U.S. broadband speed of five megabits per second.

A trial network in San Diego requires just 35 strategically located access points to collect data from smart meters and other devices equipped with On-Ramp's technology across a 4,000-square-mile area. "It boils down to a cost advantage," says Myers. "You need fewer access points this way." California utility PG&E is currently rolling out smart meters based on more established technology which will require over 1,000 access points to cover the same area, Myers claims.