When expert opinions collide, the results can be confusing.
That's the case with a pair of conflicting studies on the economic effect of closing the Columbia Generating Station and replacing its output with a natural gas fired plant.
One study estimates that continuing to operate the nuclear power plant near Richland is costing utilities more than $1 billion and the other found that the reactor is saving them more than $1 billion versus natural gas.
Who to believe?
Few of us have the technical expertise needed to conduct our own evaluation of the reports' conclusions and determine which is more credible.
But sometimes the identity of a study's sponsors can shed some light on the question of credibility. Do the people paying for the study have pre-existing positions? Or a financial stake in the eventual outcome? Too often, so-called independent studies merely justify the positions of the people writing the checks.
In this case, each study's findings supports the interests of the sponsors. The anti-nuclear group Physicians for Social Responsibility paid for the study that argues for shutting down the reactor.
The group wants to close the Columbia Generating Station for safety reasons. The economic study expands its arsenal in the war it is waging against nuclear power.
The other study, which found significant savings from continued operations, was paid for by Energy Northwest, the reactor's operator.
Deciding which study is less credible based solely on which one best supports the interests of its sponsor doesn't help much in this case. It's a wash.
Another way to gauge credibility is to consider the reputations of the experts conducting the study, but that isn't a helpful approach in this case.
McCullough Research in Portland prepared the report for Physicians for Social Responsibility. Energy Northwest's report was prepared by Cambridge Energy Research Associates in Massachusetts.
Both firms are respected in the energy field. Neither can be dismissed as second rate.
But too much about the Physicians for Social Responsibility study smells fishy to us.
The report commissioned by PSR does not take into account the costs to build a natural-gas power plant to replace the Columbia Generating Station, only the cost of operating and producing electricity at existing plants, Lawrence Makovich, one of four contributors to the CERA report, told Herald reporter Annette Cary.
McCullough denies that, but when CERA factored in construction costs, keeping the reactor was clearly the cheaper alternative.
In any case, McCullough's findings depend on assumptions about the cost of natural gas and other alternative energy sources over the next 20 years.
But the energy market is volatile, and projections decades into the future may not hold. The cost of natural gas in the Northwest since 2000 has been more than three times higher at its peak than recent lows, according to the CERA report.
Continuing to operate the Columbia Generating Station is not only economical, it helps manage risk for Northwest ratepayers, providing predictable rates, the report concluded.
But PSR's objections to nuclear energy aren't really about money.
"The report supposedly is an economic argument that gas is cheaper than nuclear, which it is at present by a very small amount," wrote James Conca, director of Columbia Basin College's Center for Laboratory Sciences.
"But if economics were the main substance, then I don't see why the report doesn't recommend phasing out wind and solar which are many times more costly than nuclear or gas," Conca continued in his analysis for Forbes.com.
The answer is simple enough. The study isn't motivated by economics but by PSR's anti-nuclear bent.
The economics aren't that impressive when considered at the household level. If the reactor had been shut down and replaced with natural gas, cost savings would have varied among Northwest ratepayers, but a Benton PUD customer would have saved about $45 in 2013, the McCullough report said.
Of course, ratepayers probably aren't paying an extra $45 a year by using CGS instead of natural gas. But even if the higher cost estimate is accurate, ratepayers are getting a good deal. For $45 they got a stable power supply, because the reactor can fill any demand that wind or hydro can't meet.
Ratepayers also get an environmental benefit for their $45.
The CERA report estimates that replacing the reactor's energy production with other sources would put an extra 60 million metric tons of carbon dioxide into the atmosphere over the next 20 years.
PSR has failed to make its case. Shutting down a reliable source of energy -- which produces enough electricity to power the city of Seattle -- doesn't make economic sense.
Given Energy Northwest's production record, there's no case to shut it down for safety concerns either.