Friday, November 1, 2013

New Nukes: The Rise of Thorium

In the context of Global Warming and climate change, the attraction of nuclear power has re-emerged among serious energy policy discussions after a 30-year hibernation.  Three Mile Island (TMI) and later Chernobyl badly chilled tolerance for "nukes", and the broader zeitgeist surrounding nuclear decommissioning in the wake of the Cold War cooled possbilities even further.  Despite well known cost considerations (read: over-runs), permitting challenges, construction delays and rampant NIMBYism, nuclear power is now receiving renewed consideration: it has the potential to provide vast amounts of electricity with comparative minor greenhouse gas emissions, especially with the popular re-emergence of an alternate fuel source, Thorium.  As a result, certain traditional opponents of nuclear power are experiencing a sort of philosophical glasnost moment, and even environmental activists--long the entrenched skirmish line against nukes--are opting for a second look.  But challenges remain.

Electricity--cheap, reliable and clean. Pick two.   In corporate project management, clients often seek a trifecta of results: a high quality work product, a quick delivery and a low budget. Corporate project managers have an axiom when responding to such requests: "You can have it good, fast or cheap. Pick two."

A similar cost-benefit trade-off tightens the turnbuckle of tension between global warming and industrial-scale electricity production.  Society can have it cheap (conventional fossil fuel), reliable (the lights come on every time we want them), and clean (low-carbon intensity, with side benefit or reduced "conventional" pollutants). But it has not, at least to date, been plausible to have all three. 

For the most part, utility scale generators have generally opted for cheap and reliable.  This trade-off has had relatively minor environmental ramifications--acid rain, particulate matter emissions, localized extraction impacts (think coal tailing ponds and Appalachian-style "mountain-topping").  The spectre of anthorpogenic global warming, however, has changed the calculus, as policy makers and electricity entreprenuers alike have aggressively sought out alternate and ideally magic-bullet energy sources.  The message has been that the clock is ticking, and irreversible climate change lurks around a not-too-distant bend on humanity's timeline.  Things are urgent, the argument goes, and a solution must be found now.

Along Comes Thorium
And a funny thing happened on the road to climate catastrophe: the once-great environmental threat from energy sector suddenly seems like a potential savior.  Not only is nuclear power getting a second look, but proponents are dusting off a technology from the second generation of nuclear reactor development and enabling a "new" type of utility-scale nuclear power.  Recent fanfare surrounding thorium-based reactors, however, suggests that a parallax shift in how we address the energy equation may be at hand.  Thorium reactors resolve several of the problems that bedevil nuclear power on a global scale:
1.  Sourcing and fuel conversion.  Thorium is both naturally more abundant than uranium and enrichment techniques are easier, effectively making thorium even more "plentiful" than uranium.
2. energy density.  Thorium contains up to 200X the energy of uranium1. 
3. weaponization.  Enriched thorium--as well as its by-products--are unsuitable for both weapons-grade and "dirty bomb" development.
4. waste remediation.  A thorium reactor can actually "burn" plutonium, eliminating it from the waste--as well as the weapon--stream).
5.  Reliance on the Imperium.  Almost 90% of known reserves are concentrated in countries that are both politically stable and economically partnered with the United States--which itself holds a 15% of proven resources.

As an added benefit, thorium reactors can be micro-sized to operate at load centers--thereby reducing expensive transmission and distribution (T&D) infrastructure.

The current accomodation for most of the industrialized world--France, certain parts of Scandanavia and Spain notwithstanding--is fossil intensive.  The commercial grid depends on extensive and complex  (T&D) systems that link central power stations to load centers such as cities and high demand industrial zones. To reliably respond to the "demand curve" that typifies most of Europe, North America and the manufacturing economies of Asia, regional and national electricity systems require a bipartite supply: base load, which runs 24 hours a day and fulfills the minimum constant level of demand on the electricity system; and marginal (intermediate/peak) load, which varies by time of day, time of year, weather and other variables and which is dispatched by a central operating authority in reponse to the demand ebb and flow. Baseload is generally fulfilled with low-cost generation such as coal plants and natural gas-powered "combined cycle" facilities. In addition to high environmental impacts, these facilities have the disadvantage of slow start-up and ramp times, and thus cannot be used to meet variable demand such as high air conditioner use on hot summer afternoons. Marginal load rely on generation types that are easily and quickly dispatchable (turned on), but that are higher cost for reasons such as start-time and fuel efficiency. So-called "peaker" units can start up in as little as 30 minutes, but burn fuel at rates that make them expensive to operate. In combination, the baseload/marginal service is highly reliable, but is requires trade-offs in either costs of operation or GHG emissions.

So the conumdrum remains. The industrialized west has extremely high demand for electricity and high population emerging economies such as China and India understand that cheap and reliable electrification is a cornerstone of modernization. Fuel is being burned at geometrically-increasing rates, which has corresponds directly with GHG emissions and threatens climate stability.

Conventional nuclear power is at best a difficult political pill to swallow and at-worst a catastrophe in-waiting.  Thorium could be the comfortable compromise.  But much would have to be done, from revised permitting processes, to a successful (and honest) public education campaign, to neutralizing the fossil fuel lobby that would oppose a nuclear renaissance.  In sum, this represents a sort of public policy Rubic Cube, where a lot of inter-linked variables would have to line-up "just so."  Is it possible?  Cynicism is justified: For a nation that split the atom, but the gridlock of entrenched interests in national politics are a force of a whole-other magnitude.


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