Tech Talk / By Martha Knight

How do you feel about rhubarb?

Most people have strong feelings about the vegetable, either for or against. I love it, and used to grow lots of it. Now I pester friends who grow it, asking for their surplus.

Perhaps my rhubarb growing friends will want to grow lots more, because could be rhubarb is the Next Big Thing.

There’s a lot of buzz about flow batteries, related to fuel cells. Flow batteries are key to energy storage to handle the energy produced by renewable sources such as solar and wind, which are intermittent.

Flow batteries are expensive to produce. But some Harvard scientists, with funding from the ARPA-E program, have announced what they think is a solution to the expense problem.

It’s all about quinones. When I started reading about them lately, the first thing that popped into my mind was hydroquinone, an organic compound that is in skin lighteners, used for dark spots and even to lighten skin generally (probably a dangerous misuse of such products). It inhibits melanin production.

The quinones the Harvard scientists are studying in their flow batteries development project are not hydroquinones, but are described as “naturally abundant, inexpensive, small organic (carbon-based) molecules.”

We knew they’d be small, didn’t we! But these are small even for molecules. And they are inexpensive compared to what? What is it that makes flow batteries expensive? Vanadium. It’s the active metal component that is dissolved in the rechargeable electrolyte solution stored in tanks, to be pumped into cells to react electrochemically across a membrane to make current.

Eliminate the need for vanadium, and find something that does the job but doesn’t cost as much, and flow batteries can become what all our favorite products are claimed to be, in all our favorite commercials: affordable.

If quinones will do the same thing as vanadium, but at a lower cost, we hope there is an abundant source of quinones. Preferably a renewable source.

There are quinones in crude oil. But the planet is not producing new crude oil rapidly. Humans keep extracting the crude that has been made a long time ago, and sometimes finding more in places they didn’t know it was, but it isn’t what we call renewable.

Quinones are also in green plants. The molecule used to make the flow battery the Harvard team is telling about is almost exactly the same as the one in rhubarb

Renewable energy can be scaled easily by controlling the size of the tanks holding fluids that are pumped into cells to make current. That scalability isn’t a feature of solid-electrode batteries.

Suppose you have a 1-megawatt capacity wind turbine, and you need to be able to store 50 hours worth of its production. One way to go would be to buy regular batteries with 50 megawatt storage capacity. You might not need all that capacity. It would be nice to be able to buy just the storage capacity you need. With flow batteries, that means fluid tanks of the appropriate size. You can always add more later if you want more storage capacity.

A family might have its own wind turbine and need a small tank for its flow battery, possibly underground or in a basement. A power company with a lot of wind turbines on a giant wind farm would need big tanks—probably not a large number, but a few very large tanks.

We notice LP gas tanks sitting behind some homes out in the country. But the time may come when we will see tanks about that size, for storage of the energy from the solar panels on the roof of the home.

Quinones are dissolved in water to enable that process. Good thing, too. Otherwise they might ignite. So that’s why some people claim rhubarb gives them heartburn!

Much as I like the idea of there being a renewable source of quinones for affordable flow batteries for storage of renewable energy, I am concerned about a possible shortage of rhubarb, or a sharp increase in the price, or both. Remember what happened to the price of food, including meat, dairy, cooking oil, and of course other food more obviously based on corn, all because of ethanol?

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Polaroid. Remember the instant photograph company, and Polaroid-Land cameras and film packs? Several even guest starred, along with Dick VanDyke, in a Colombo episode.

Well, the company unveiled an interesting new concept in cameras at the recent Consumer Electronics Show in Vegas.

The Polaroid C3 is a tiny camera in a cube housing. It has a magnetic skin, so it can be mounted on anything metal. It’s high-definition, wifi capable, and has a wide-angle lens—120 degrees. Waterproof too, down to 6.5 feet.

And it costs $99.