Converting old pulverized coal power plants to use advanced solid biofuels rather than coal provides a ready-to-go solution for compliance with states’ renewable portfolio standards (RPS).  The strategy delivers low-carbon and low-cost electricity that will also satisfy the EPA’s proposed carbon policy under section 111(d) of the Clean Air Act and the Clean Power Plan.  This strategy is the lowest-cost pathway to compliance and provides a renewable solution without the intermittency of wind and solar.  The strategy does not cost jobs.  In fact the strategy creates new jobs.

Most coal fired power stations are pulverized coal plants.  Those plants convey coal into pulverizing machines that crush the coal into a fine powder.  That powder is pneumatically conveyed from the pulverizers to the burners.  The burners are mounted in the sidewalls of the power boiler.  The coal dust is blown into the burners and combusts very rapidly; almost like a liquid fuel. 

Two years ago, the concept of using pulverized wood pellets in large coal fired power stations to completely replace coal was unproven.  That has changed with three large power plants proving that using pellets in power stations not only works, but allows the power station to consistently and reliably generate the same amount of electricity as they did with coal (Drax in the UK and Ontario Power Generation’s plants in Atikokan and Thunder Bay Ontario).   There is no derating of the power plant.  Just as many megawatts can be generated from the renewable low-carbon fuel as from coal.

Although the EPA’s carbon policy that would incentivize high carbon emitting power generators to mitigate their CO2 emissions is a few years from implementation, 27 U.S. states do have renewable portfolio standards (RPS).  11 other states have variants on RPS.  RPS goals apply to 55 percent of retail electricity production in the US.  The RPS systems provide incentives to the generators by issuing renewable energy certificates (RECs) for each MWh generated from renewable sources.  RECs are traded in the open markets and have values ranging from a few dollars to over $50 per REC. 

The pathway to that lowest-cost renewable power for RPS and EPA section 111(d) compliance that also has the benefits of being available on demand (dispatchable) or continuously (baseload) is via the conversion of older pulverized coal power plants into updated facilities that run on advanced solid biofuels. 

Thermal generating stations that can be switched on as needed can complement the wind and solar component of the renewable low-carbon power portfolio.  Every MW of wind or solar power needs a MW of thermal generation (or hydro where available) to keep the grid balanced when the wind is not blowing and the sun is not shining.

Converting from pulverized coal to advanced solid biofuel will have a significant positive net job impact in the fuel supply chain.  The typical argument against renewable power solutions such as wind and solar is that they will result in a higher electricity price placing a drag on economic growth.  Wind and solar generation results in significantly higher power prices than power generated from plants converted to use pellets; and wind and solar are a generation pathway that requires no labor for fuel provisioning. 

The best solution for new renewable power generation that has baseload and peaking characteristics is the conversion of older pulverized coal plants from coal to renewable low-carbon advanced solid biofuel.  When there is a carbon policy in the U.S., the converted plants will already satisfy low-carbon requirements.  For every MWhe not generated by coal, on average, about 1400 pounds of CO2 is not emitted.  For a 500MW power station, that adds up to about 3,000,000 tons per year.

Wood pellet supply chains are well-established.  The quantity of power that can be generated is limited to the sustainable quantities of renewable woody biomass.  However, within that sustainability boundary, a significant proportion of older pulverized coal plants can be converted. 

Many new pellet manufacturing projects could be developed if the demand were to increase.  There is no shortage of sustainable feedstock in the fiber baskets of the U.S. and Canada. 

This is a strategy that does not need R&D, does not need massive subsidies, and does not need any significant infrastructure investment.  The fuel supply chain is already well-established
Pellets offer a low cost, low carbon, reliable, ready to deploy, renewable solution to our peaking and base load power demand that will result in the creation of more jobs than any other power generation technology.

Author: William Strauss
President, Future Metrics
www.futuremetrics.com
williamstrauss@futuremetrics.com