Many industrial processes operate 24 hours a day, so they require constant heating. By carefully controlling the heat transfer, the Ronodo system is powered by renewable sources, so it can charge quickly using short periods when electricity is cheap. The starter heat batteries require about four hours of charging to be able to provide continuous heat throughout the day and night.
One of the main challenges of thermal storage technologies is building enough systems to meet the huge energy demand of heavy industry. Rebecca Dale, senior industry director at ClimateWorks, said the sector was experiencing “horrendous” temperatures. Three quarters of the energy used in industry each year is in the form of heat, today only one quarter is electricity. Industrial heat accounts for 20 percent of the world’s total energy demand.
Fossil fuels are the obvious, most economical way to power these massive industrial processes, but the cost of wind and solar power has fallen by more than 90% over the past several decades. Dell says this opens the door for electricity to play a bigger role in industry.
We are in this wonderful time where we can stop burning things for warmth And Be cheap,” says O’Donnell.
There are a few other options for using cheap renewable energy in industry. Some appliances can be adjusted to use electricity directly instead of high heat. Companies are working on electrochemical processes to produce cement and steel, for example, although replacing all the infrastructure in existing plants could take decades. Using electricity to generate hydrogen that can later be burned for electricity is another alternative, although in many cases it is still cost-effective and inefficient.
Any effort to meet the industry’s high heat demand will require a dramatic expansion in electrical power. A typical cement plant uses 250 megawatts of energy, mostly in the form of heat, Dell says. This is energy worth about 250,000 inhabitants, so electrifying a large industrial facility means an increase in electricity demand equal to that of a small city.
One brick at a time
Rondo is not alone in its efforts to industrialize thermal batteries. Antora Energy in California is also developing thermal storage systems using carbon. “It’s very simple — it’s literally just solid blocks,” says founder and co-founder Justin Briggs.
Instead of using a separate heating element (like Ronodo’s “toaster coil”) to convert electricity to heat, Antora’s system uses carbon blocks as resistive heaters that both generate and store it. This can reduce costs and complexity, Briggs explains. But the choice of graphite and other forms of carbon means that the system must be carefully connected, as the temperature in the air decreases.