As Japan recovers from the spring tsunami and Fukushima nuclear station disaster, it plans for a clean energy future. It is tempting for its energy industry officials to categorize all the lessons of the nuclear crisis as specific to the atomic energy industry. Accidents happen, however, in all complex energy production systems. Accidents in the most abstruse technology systems, from commercial airplanes to tankers to space shuttles to nuclear plants, can overwhelm even the most conscientious designers and operators.

As Japanese clean energy hardware makers Toshiba, Panasonic, and Sharp expand production and design prototypes to meet a new national demand for renewable energy, they should heed one of the lessons of the nuclear industry: keeping it simple keeps it safe.

In Normal Accidents: Living with High-Risk Technologies, Yale sociologist Charles Perrow posits that modern technology systems contain so many connected, interactive parts that accidents are inevitable and natural during their operation. Thus he calls these events “normal accidents.” For certain, corporate malfeasance in the nuclear industry—falsification of safety records, for example—is still culpable when it occurs.

One of the most ignominious examples of nuclear industry negligence came in 1987 at Philadelphia Electric’s Peach Bottom plant. The Nuclear Regulatory Commission shut down the plant when they found evidence of control room shenanigans during the night shift: sleeping on the job, playing video games, and rubber band and paper ball fights. The nuclear industry’s self-regulating body, the Institute of Nuclear Power operations, sent a letter to Philadelphia Electric’s board of directors. Its message echoed the sentiments of the public and the industry: “It is an embarrassment to the industry and to the nation.”

Perrow’s point is that even under a perfect safety regime, normal accidents happen when the technology is sufficiently complex. For certain high technologies like nuclear plants, “neither better organization nor technological innovations appear to make them any less prone to system accidents. In fact, these systems require organizational structures that have large internal contradictions, and technological fixes that increase interactive complexity and tighten the coupling; they become still more prone to certain kinds of accidents.” When the U.S. commercial nuclear power industry began in the 1950s, many plant owners wrongly assumed that coal and oil plant operation logs would tell them all they needed to know about nuclear safety.

Yet, a typical nuclear reactor has forty thousand valves, ten times the number of a coal plant. Small actions produce unexpected consequences across feedback loops of such magnitude and variety as to be incomprehensible. In a recent column in Bulletin of the Atomic Scientists, Jungmin Kang wrote of the Fukushima accident, “What really [emphasis in original] caused the accident, however, was that the power plant simply ran out of electricity.” The loss of power spiraled out of control and panic ensued.

Consider historical nuclear plant accidents in the U.S. that began small but escalated due to the integration of the system components. Three Mile Island, the prime example, was the product of an improperly closed valve and a stuck water level gauge, among other errors. But there are many other examples.

In 1980, a worker at the North Anna Unit 1 reactor in Virginia accidentally caused a reactor shutdown by catching his shirt on a circuit breaker. In 1975, a worker at Browns Ferry Unit 2 in Alabama used a lit candle to check sealant integrity and accidentally started a fire; the blaze damaged over a thousand electrical cables and forced staff to shut down the reactor. In 1978, a worker at Rancho Secco Unit 1 reactor in California accidentally dropped a light bulb, causing a short circuit and reactor shutdown.

Even the slightest problems with piping can lead to disaster if radioactive water is sent to the wrong area of the plant. Most nuclear plants depend on cooling water supplied by nearby rivers and bays—ecosystems full of animals and plants. Clam colonies can stick to cooling pipes in nuclear plants, eventually clogging them. Then workers must clean the clams from the pipes while the plant is shut down.

Perrow’s theory merits study as Japan builds a new, greener energy policy. Energy safety and security is paramount for wind, solar, hydropower, and other clean sources if their advocates are to gain the public trust and private investment required to expand.

Right now, all of these renewable sources are safe to operate. The most successful stories seem to come from small, local production like solar roofs and geothermal home heating. But their proliferation as base-load electricity sources will likely require mass scale energy storage. Batteries, as we now know them, can explode, corrode, and ignite.

Sony’s introduction of the first lithium-ion battery in 1991 was followed by a quick recall when a pack in a cell phone emitted hot gases that burned a man’s face. Battery technology is certain to evolve and proliferate in fantastic ways as renewable energy matures as an industry. Solar, wind, and geothermal technologies have much room to grow. In 2007, Japan generated only 6 percent of its primary energy from renewable sources. On May 25th, Prime Minister Naoto Kan announced plans to boost that number to 20 percent by the early 2020s.

The Intergovernmental Panel on Climate Change recently calculated that more than 97 percent of global renewable energy potential remains unexplored. As the clean energy industry expands, widespread battery use could threaten human health and energy security. By 2050, scaled up in grand fashion, the clean energy industry could suffer from the tight coupling and interactive complexity that causes normal accidents in the nuclear industry. We cannot conceive how complex the wind farms of the future will be—the number of moving parts, batteries, and circuits necessary to power, not just towns but nations.

Granted, no disaster at a solar or wind plant could match the horror of a nuclear meltdown. But blackouts are destructive enough to our economy and our health and can exacerbate other crises. And even if the renewable energy sector expands at the rapid speed Japanese politicians prefer, the nation will depend on nuclear plants for the short term to provide base-load electricity as renewables meet peak demand.

The dirty and clean energy industries are more interdependent than their leaders would care to admit when it comes to building a culture of safety. Japanese industrialists eager to guarantee a safe green energy future should study their nuclear past.