The March 11, 2011 Fukushima Daiichi nuclear power plant disaster has precipitated a world of change in Japan's nuclear power industry.

Within hours of the 9.0 earthquake and tsunami, most of Japan's 54 nuclear power plants (which had supplied 27 per cent of Japan's electricity) were shut down on orders from then Prime Minister Naoto Kan.

Japan is now burning fossil-fuels to replace the missing electrical generation capacity and has recently signed an agreement with Saudi Arabia to purchase three times their total 2010 oil imports.

In the interests of public safety and for the peace of mind of residents who live near the numerous and widely-scattered nuclear plants in Japan, the government has ordered "stress test" inspections of all nuclear plants in the country.

Even so, due to rising political pressure from ordinary citizens and the growing anti-nuclear power protest movement there, not every plant which has been "stress-test approved" may restart.

With those daily Japanese newspaper headlines in mind, the government of Japan and power plant operators are discussing the lengthy and hugely expensive decommissioning process for the Fukushima plant, which may take more than 40 years to achieve, at a cost estimated to between 15 and 45 billion (US) dollars. It looks like the Japanese taxpayers are stuck paying for the full decommissioning cost.

As you may be aware, Germany is decommissioning all of it's nuclear power plants by 2022 -- although in typical German fashion, they are ahead of schedule.

Many of Germany's nuclear power plants are decades old, problem-plagued, and would have required a staggering amount of investment to meet contemporary safety standards. In Germany's case, it was less costly over the long term to employ a temporary feed-in tariff scheme to speed earlier adoption of green energy, rather than constantly upgrade 17 old nuclear reactors to ever-changing standards.

Italy got out of the nuclear business in 1987 as the costs to retrofit their old power plants with better technology exceeded any profit they would have realized during the rest of their power-producing lifetimes. Switzerland has committed to scrapping their nuclear power program by 2045.

The United States, Russia, and Canada are all in the same boat -- as they continue to operate many old, lower-tech, and very costly to upgrade, large nuclear power plants.

However, a new hope for the nuclear power industry has arrived in the form of a brand-new nuclear power plant design -- known as small scale "modular" nuclear reactor, which is a profoundly better answer to the ultra-costly retrofitting of very old and large nuclear plants -- and long overdue for most of the world's reactors.

Modular reactors are much smaller (never larger than 300 megawatts) and are almost innocuous-looking when compared to the monster-sized nuclear power plants of the 1960s and 1970s. Best of all, they all feature 21st-century architecture with many "simple" redundancies built right in, such as gravity-fed cooling systems which remove the problem of cataclysmic coolant pump failures as has happened at Fukushima and other nuclear disasters. Modular nuclear reactors will be the future of nuclear energy and it turns out that the U.S. will be the first adopter.

Two large conventional nuclear power plants, now under construction, will be completed in the U.S., replete with the latest safety systems and some design elements borrowed from modular nuclear reactors -- at the nuclear power plant in Votgle, Georgia, and a smaller unit in North Carolina. After those plants go online, it is expected further U.S. plants will be small scale modular nuclear reactors between 45 and 300 megawatts -- tiny by nuclear power standards.

The modular nuclear reactor -- with its low profile, easy location requirements, small nuclear fuel and water appetite, low installation costs, easy grid connection, uber-safe design, and ability to generate both power and profits in a dramatically shortened time frame -- is going to be a tough competitor to beat.

The brilliance of modular power plants is that they mesh seamlessly with PV-solar, and wind turbine power. Along with sustainable energy, the dream of "all clean electricity -- all the time" is at the very least within our grasp.

By the time those nuclear plants in Germany have been completely decommissioned by 2025 or so, we should be at "all clean electricity -- all the time" in most of the industrialized world. Modular nuclear reactors will be an important and welcome partner of sustainable energy.

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