Is CHP really one of the next big things?
By: SGN Staff
By Doug Peeples
SGN News Editor
We tend to think of combined heat and power as a relative newcomer in the energy world, but it's far from new. The concept of using waste heat, a byproduct of generating electricity, for heating and cooling has been around since the 1880s. It's just that we're a lot better at it now and it fits in nicely with the overall smart grid initiative.
Also referred to as CHP and cogeneration, the frequently complicated technology has had its ups and downs since it was first used, but has become more popular and promising than ever. The attraction is that while CHP uses both fossil and renewable fuels to produce energy or mechanical power and (and heating and cooling), it does it much more efficiently than traditional separate heat and centralized power systems, according to the Center for Energy Efficiency & Renewable Energy.
The center, based at the University of Massachusetts Amherst, offers an impressive list of benefits provided by CHP in the U.S.:
Â· Produces more than 9% of the electric power produced
Â· Saves users over $5 billion every year in energy costs
Â· Cuts energy use almost 1.3 trillion BTUs annually
Â· Reduces nitrous oxide emissions by 400,000 tons and almost a million tons of sulfur dioxide annually
Â· Prevents the release of more than 35 million metric tons of carbon equivalent into the air
Is CHP really that big a deal?
Those benefits have mostly come from large industrial plants like those used to produce paper, refining and chemical processes. But the numbers mentioned above coupled with the promise of vastly improved energy efficiency have brought CHP a lot of attention in an era when industrial distributed generation (industries developing their own on-site power generation) is growing and getting a lot of both public and private support.
Who's using CHP and what are they doing with it?
Iceland, Italy, Germany, Turkey and other countries use CHP with renewable geothermal energy and send the heat to district heating grids. There are numerous examples all over the world and hundreds in the U.S. alone of how CHP is being used.
We'll use Illinois, a completely random pick, as an example. Not only is CHP used in industry and agriculture, it also can be found in schools and universities, hospitals, a museum and the Great Lakes Naval Station, according to DOE's Office of Energy Efficiency & Renewable Energy which offers exhaustive statistics on CHP projects throughout the country. Nationwide, CHP also can be found operating at big box retailers, single and multi-family residences (where it's referred to as resCHP), hotels, recreational facilities and so on.
And the list includes some pretty big names: Pepsi, Gillette, Pfizer, Siemens and, of course, oil companies such as BP and Exxon/Mobil.
According to EERE, there are 464 projects in New York, 124 in Texas, 60 in Oregon, 55 in Minnesota, 17 in Nebraska and Arizona - just to give you a feel for each region of the country. While natural gas seems to be the fuel of choice, CHP plant operators also use wood, other biomass and coal.
If you want examples of specific CHP projects, here are a few to look at:
What? No downside, no drawbacks?
Yes, there are drawbacks and the potential for failure, mostly in the design phase. The American Council for an Energy-Efficient Economy probably sums up those issues best in its comprehensive, 'everything you could possible want to know' CHP toolkit:
"CHP systems can be complex and involve many players, so it is critical that system designers consider and plan for the many regulatory and logistical hurdles that may emerge. CHP systems can fail to produce their claimed benefits if they are poorly designed, constructed, or operated, so it is also important that prospective CHP users undertake substantial due diligence to ensure that a new CHP system is properly designed to meet the local power needs and will be constructed and operated as planned."
ACEEE is right of course. But those cautions could be said of most complex technology applications: if something's not right at the start, it's not going to get any better as a project rambles toward implementation. We'd like to think most companies, utilities, local governments and others interested in CHP are aware of the possibilities for failed projects - and that they aren't going to invest in half-baked designs.
The need is there and the markets and opportunities are there, so it looks as if CHP can only continue to grow.
A bit more on CHP ...