The Power Grid Is Getting Bigger, But Plants Are Shrinking. That is a Bloomberg News headline. (Below)
Seems contrary, doesn’t it? But it is true and has a lesson about our energy future.
Key paragraph in the story: “All these power generation technologies – from a meticulously engineered gas turbine weighing 80% more than an Airbus A380 to solar power generators with less than a ten-thousandth the generating capacity – complement each other, but they compete on the margin. It’s not just a feud between renewable power and combined-cycle gas or coal, either; it’s also an evolving rivalry between batteries storing generated power and peaker gas plants that make them unnecessary.”
Books can be written based on that paragraph. We will restrain ourselves.
The long-and-the-short of it is the big-and-the-small sources of energy.
The story starts with the delivery of a state-of the-art gas turbine used to make power. Siemens makes this neat machine. (Siemens has a manufacturing plant in Charlotte, BTW.) Duke Energy’s Illumination website has a good story about this kind of turbine because the company uses it near Lincolnton, NC.
“A combustion turbine generator operates like a jet engine, drawing in and compressing outside air to a high pressure. The pressurized air mixes with natural gas and then burns, creating hot exhaust gases. These gases power a turbine, spin a generator and ultimately make electricity. What makes the Siemens’ combustion turbine advanced is the way it burns fuel, coupled with the shape, aerodynamics and thermal dynamics of its blades,” says Illumination. (Right)
Benefits of a natural gas turbine are that it has a fast ramp-up to produce power and when matched against cola plants it produces fewer emissions. Plants like this are the swing producers of the energy world to make sure the grid has enough power to meet demand.
Natural gas as a fuel has its critics, though. It is a fossil fuel, so there are some emissions.
The Bloomberg story says that this kind of machine, as great as it is, will not dominate the future of energy. To quote a Disneyland ride, “It’s a small, small world.”
Turbines like this may be too big for the future. Renewable energy isn’t growing by single sites making huge amounts of power, but a lot of smaller solar or wind units that aggregate into a lot of power. Solar. Wind.
Renewable energy will be the fastest-growing source of electricity generation in 2020. The electric power sector will add 23.3 gigawatts (GW) of new wind capacity and 13.7 GW of utility-scale solar capacity in 2020. (Source) By the way, one GW is about 3.125 million photovoltaic (PV) panels, or in more old-fashion terms, 1.3 horses. (Source) Or, enough to power more than 700,000 homes. (Source)
Placing numerous renewable energy sources also means that the grid must accommodate the new system. Central generation has been the hub and spoke grid system that has been use din the past. Now we might say there is a spoke-to-spoke-to-spoke-to-spoke system coming of age.
Many small generation locations will serve small users. Seems almost quaint, really. “There is a new emerging trend in renewable energy with a rather idyllic sounding name: energy communities. These communities are designed as a model for the brave new world of producer-consumers – individuals that not only take energy from the grid, but feed back into it via their personal energy production devices, most commonly solar panels.” (Source – left)
Remember that small energy facilities are not just about making energy: “It’s also an evolving rivalry between batteries storing generated power and peaker gas plants that make them unnecessary.”
Energy storage is a wild card, the ability to store solar power when the sun is out, for instance, and pump it into the grid later. What kind of storage? Not large-scale storage, like a nuclear or gas plant, but the cumulative resource created.
That gets us back to the beginning of the blog. The grid, or web, seems to be increasing as it reaches out to new, numerous and smaller sources of power. What a grid we weave!
Check this Siemens infographic about its turbine workhorse. (Feature image from Siemens.)