On the third anniversary of the Fukushima nuclear disaster, engineers have hailed the technology that has risen from the ashes.
The world’s worst nuclear incident for 25 years was set in motion on 11 March 2011 after a tsunami, triggered by an earthquake off Japan’s Pacific coast, caused a series of explosions and meltdowns at the Fukushima Daiichi nuclear power plant that spewed radiation over a huge swathe of Fukushima prefecture.
An 18.5 mile radius around the plant was declared a no-go zone, forcing 160,000 people from their homes. In other areas where the radiation was not so critically high the authorities took steps such as replacing the earth in parks and school playgrounds, decontaminating public spaces such as sidewalks, and limiting children's outdoor play time.
Despite the massive human cost, not to mention the estimated 1.15 trillion yen (£6.7bn) it will take to decommission the stricken plant's four reactors, some of Japan’s leading engineers have highlighted the technological advances that have come out of the disaster.
Hiroshi Nishizawa, chief researcher at the Mitsubishi Electric Corporation Advanced Technology R&D Centre, said: "Over the past three years, scientists have made huge leaps in taking already known principles and technologies, and turning them into real things that people need.
"So there were no groundbreaking discoveries, but you do need to remember that no matter how great a discovery, a number of walls stand between it and making it something you can hold.”
In particular, Nishizawa points to the development of systems capable of detecting tiny amounts of radioactive material in a short amount of time and gamma cameras capable of taking images of radioactive contamination.
“In both cases, a clear motivator has been that people in the devastated areas needed this technology as soon as possible because it had significant effects on food safety and living environment quality,” he said.
Essential for these systems are scintillators – materials that produce flashes of light when excited by ionising radiation. According to Professor Hiroyuki Takahashi of the Department of Nuclear Engineering and Management, University of Tokyo, fundamental research into these materials has been one of the biggest beneficiaries of the disaster.
He said: “In terms of fundamental development of scintillators and compound semiconductors, more industries and scientists are working on improving it, and I think we can expect to see more improvements in this area in the future."
Another field to have benefitted greatly from the disaster is robotics. According to Professor Hajime Asama at the Department of Precision Engineering, University of Tokyo, more than 30 types of robotic devices are being used in the clean-up operation.
"Very few robots were ready to be used straight after the earthquake and the nuclear accident so, in the beginning, emergency and military robots were brought in from overseas,” said Prof Asama, who is currently chairman of the Robotics Task Force, and a committee member of the Government, TEPCO Decommissioning, and Contaminated Water Response Team.
“Later on, Japanese researchers started to develop and send in robots tailored to the needs of people inside the disaster zone. These included robots for measuring things, carrying out light work, flying robots, and aquatic robots. It was proof Japan could produce robots people needed," he added.
"With decommissioning expected to take another 30 to 40 years, it's not an exaggeration to say its success and failure depends on robotic technology development.”
Among the roles taken on by robots are irrigation, clearing rubble, measuring the amount of radiation, taking video footage, taking samples, decontamination, protection, and transporting equipment.
“It's already clear scientists still have to invent robots capable of detecting, measuring, and cleaning up the contaminated water, and robots able to withstand extreme conditions such as high pressure or high radioactivity,” said Prof Asama.
"It's also important to prepare for the next big disaster. To do this, we will need to have remote-controlled devices and robots on standby at all times – and even, perhaps, establish an emergency response robot centre."