Today’s holy grail of energy research isn’t fusion. It is simply finding a better way to store electricity.
Much of the grid-based electricity in the U.S. is stored in water towers. These are a common feature of the American landscape, yet most people believe they just store water.
Here is how they really work: Utilities use excess power to pump water up into the tower, and gravity pulls water back down when power is needed. A small hydropower turbine at the base converts the flow of water back to electricity. If this sounds a little primitive, well, maybe it is.
There is a better way to store electricity. This is what batteries are made for.
The first rechargeable lead-acid batteries were invented in 1859. They were used in early automobiles, but they suffered from problems with weight and poor energy density. Nickel-cadmium batteries came on the scene in the late 1890s, but they were expensive.
Sony introduced the first lithium-ion battery in 1991, after decades of research. Today, we are still using those batteries to power everything from watches to laptops and cars. Tesla (ticker: TSLA) recently “bet big” on lithium-ion technology with its Nevada-based Gigafactory.
However, there are better alternatives on the horizon.
The battery landscape
Solid-state batteries are already being produced in Japan by TDK Corp. (TTDKY) and are miracles of miniaturization; some are the size of a grain of rice. While most batteries have a liquid electrolyte to transport charged ions between the anode and cathode, solid-state batteries use a material more similar to glass, which reduces the risk of catching on fire. They also use lithium-based anodes instead of graphite, which can hold up to 60% more change in the same volume.
Tesla and its Powerwall division are working on ways to store electric production from residential solar panels. However, these aren’t practical for utility-scale electric storage. They are just too expensive and wear down too quickly.
As a possible solution, researchers at the University of Southern California are making progress with flow batteries. In this case, positive and negatively charged chemicals are stored in separate tanks. Those chemicals are pumped through an ion-exchange membrane to filter out the electrons, which push the electric current.
This research is in a very experimental stage. Scientists are experimenting with low-cost water-based electrolytes and quinones as alternatives to expensive and toxic vanadium-based batteries.
The most far-out battery designs by far are coming out of MIT. Angela Belcher and her team have created batteries from genetically engineered viruses. This “grow your own” battery matches the performance of today’s lithium-ion batteries in terms of power storage, but it loses capacity after a hundred charge cycles. Belcher points out that the virus-based batteries are moldable and strong enough to be used as a replacement for plastic in dashboards and door panels.
Supercapacitors have the benefit of being able to charge and discharge electricity much more quickly than a conventional battery. This gives them an advantage when quick refueling times are important. They also perform better in cold weather and can go through more cycles of charging and discharging. Tradeoffs do exist, including lower energy density and the inability to hold a charge for more than a few days.
Fuel cells offer an interesting alternative to battery technology by storing vast amounts of hydrogen molecules. When hydrogen is burned in the presence of oxygen, it produces H2O1 — yes, pure drinking water. It is a cleaner, better alternative to gasoline. Fuel cells can also fuel more quickly than batteries, are much lighter, and have longer driving range. Current uses are generally limited to supplying local transportation — city buses, forklifts, and factory carts.
How hydrogen plays a key role in renewable energy
Aside from being a convenient way of storing energy, hydrogen gas is also very easy to make. Electrolysis is a typical high-school science fair experiment. It is simply the process of sending an electric charge through water to separate oxygen from hydrogen.
In this way, clean hydrogen can be made via renewable sources (wind, solar, hydro and wave). Energy is stored in the form of a molecule, which can be sent through pipelines instead of electrical wires.
The idea here is sector coupling, or using existing natural gas infrastructure as a storage and distribution solution for next-generation hydrogen. The pipes are already in the ground, so less investment is required. It is also a great way to buffer the over- or underproduction of electricity from renewable sources.
Overseas, the European Union is leading the way and has committed up to 30 billion euros to produce 1 million metric tons of green hydrogen per year.
Delaware is a layer in the new energy revolution
Bringing this back into our backyard: Newark is becoming a surprise powerhouse of post-petroleum power generation and storage technology. W.L. Gore holds a key patent for proton-exchange membranes, a crucial component for most of today’s hydrogen fuel cells.
University of Delaware Center for Fuel Cells and Batteries has been running a hydrogen-powered bus for years, and is now researching competing ammonia-based and methanol-based fuel cell technologies.
In 2019, W7Energy, the Delaware Innovation Space-based startup with UD-developed technology, was awarded $3.4 million in funding from the U.S. Department of Energy.
Meanwhile, a nearby Bloom Energy factory enables distributed production of electricity through natural-gas powered “Bloom Boxes.” (Caveat: The Silicon Valley-based company’s disruption plans have hit a snag.)
The new “electric age” is being transformed by innovations in science. And it looks like the tiny state of Delaware is playing its own role.-30-