Coal, Gas, Renewables

Hybrid Power: The Relevance of Gas in an Increasingly Renewable World

Issue 1 and Volume 119.

Tim Miser   By Tim Miser, Associate Editor

I once stayed overnight in an apartment with a fake fireplace. If you’re like me, when you hear the phrase “fake fireplace” you immediately develop a certain picture in your mind. I’m not going to tell you if I like fake fireplaces or not-I don’t-and it’s beside the point whether you feel that fake fireplaces are chintzy or merely convenient. The point is, when you hear that phrase, you inevitably conjure up a particular mental image-fake logs, painted ashes, an artificial glow, all there to create the impression of a log fire, albeit one whose heat is actually derived from natural gas.

The fake fireplace in this apartment was not so different. It relied on natural gas for its flame and associated heat, and it employed an artificial facade to trick the eye into believing it was something it was not. The only difference was, instead of imitating an old-fashioned wood fire, this particular fireplace pretended to be an even older-fashioned coal fire, circa merry old Victorian London, with large chunks of fake anthracite piled up to create the illusion of an ample supply of mined fuel.

Even at the time, I found this scene curious. Never mind that I nearly blew up the apartment trying to light the ancient contraption; it stuck in my memory. It wasn’t until I began my editorial career in energy that I realized just how ironic this picture was. Here was a natural gas installation masquerading as a coal-burning appliance. You won’t find many gas-fired power plants doing that these days.

No, gas-fired power plants are proud facilities lately, and it seems the days of coal-fired generation are numbered. (At least no one expects to see a new coal plant being built anytime soon.) In this respect, natural gas is the relative new kid on the block-the cleaner, more efficient hero of the environment, the savior of well-lit dining rooms everywhere. Or it was until those punk upstarts in renewable energy stormed the stage.

Anymore it seems that natural gas-fired power plants are themselves feeling a little threatened, and this time it’s renewable energy’s fault. Perhaps, though, natural gas-fired plants shouldn’t feel quite so vulnerable. Renewable resources like wind and solar represent important innovations in the energy industry. In the very long term they may even prove to be the dominant force in the market, but it seems unlikely that they will ever entirely supplant gas generation. This is good news for a lot of people. It means that renewables should not be seen as obstacles, but as opportunities, and many utilities and power plants are seeing them as just that.

Hybrid power plants-those that couple traditional fossil generation with renewable technologies like wind or solar-are being developed across the country. In many cases, these projects do not represent entirely new installations, but existing fossil plants that have chosen to add renewable resources to their extant facilities. Such a proposition can be enticing. Renewable add-ons are typically cheaper than their greenfield counterparts because they can share certain components like controls, valves, and transmission lines with the fossil infrastructure to which they are retrofitted. Other factors driving the addition of renewable assets include the potential for carbon pricing in the future and the renewable portfolio standards being adopted by many states.

Of course, it’s not just fossil plants that benefit from hybridity. Renewable technologies also benefit from their relationship to fossil plants, in that their much-decried intermittency issues can be effectively mitigated by their more reliable fossil brethren. In this way, hybrid power plants are like hybrid cars. They can utilize their clean renewable technologies when it is advantageous, and depend on their fossil technologies when renewable options prove infeasible.

Currently more than 80 percent of power generated by the average hybrid plant comes from traditional fossil fuels like natural gas, with the remaining power being generated renewably. But it’s reasonable to anticipate a time when this dichotomy will find greater equilibrium, and renewable resources will shoulder a greater portion of the load. Predictions are tricky things, and more than one prognosticator has been made to look foolish by history. (I once saw a 1950s-era prediction that personal computers would somehow incorporate a bus-sized steering wheel.) Renewables may merely supplement natural gas indefinitely, or if the tables turn in our Jetsons-like future, natural gas might one day rank second in capacity to solar and wind. In the coming decades the two might even find some semblance of parity. Whatever the case, gas-fired generation will have a place in the energy markets for a very long time.

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