Moving Data Over Power Lines Aims to Boost Green Energy
Sending messages about shifts in the price of power allows utilities to maximize renewables.
A new experiment demonstrates that it’s possible to send data across a country’s power grid—a finding that might make it possible to build virtual power plants to make better use of renewable energy.
Virtual power plants are software-enabled systems that tie together electricity from numerous renewable sources so that it can be sold at varying cost by a central body. It’s a clever way to regulate supply from power sources that are by nature sporadic.
To date, such schemes have been demonstrated only as small-scale trials. Notably, the German utility company RWE has shown that it’s possible to combine supplies from wind turbines and rooftop solar installations to provide a steady flow of electricity. And more recently a project in New York has combined solar panels on 300 homes to create a 1.8-megawatt virtual power plant.
Making virtual power plants work at the national level, though, will require all of their components—distributed renewable sources, a centralized software system, and devices consuming power—to communicate with each other. So a new experiment in the U.K. provides hope for the blossoming of these virtual networks.
The trial, which the Guardian claims is the first time that data has been successfully transmitted across a national-scale power grid, has been carried out on the U.K.’s National Grid using systems developed by a company called Reactive Technologies. The approach modulates the 50-hertz AC signal in order to send messages over the infrastructure. During the experiments, huge resistors were used to generate messages in the signal, which were accurately recorded by detectors scattered around the grid.
The technique could prove useful. A virtual power station could announce to the network when prices are decreasing or increasing, prompting devices to consume more or less power. A pump at an industrial site, for instance, might work harder when the price falls below a certain level, or a thermostat might gently adjust its set point when prices rise too far. That way, demand could be controlled by simply alerting devices to changing market conditions.
While the first tests of the approach will be carried out in commercial settings, it’s easy enough to imagine it being used in people’s homes, too. Unlike smart-metering systems, the company claims, the technique doesn’t interfere with privacy, because consumers’ devices only receive messages, never send them. It also means that devices don’t have to be Internet-connected to take advantage of the supply announcements.
The first commercial customers are expected to start using the service within 18 months. Actually, not virtually.