People like to say history repeats itself, but Southern Co., which is building the first U.S. nuclear reactors approved in decades, is hoping this isn't true.

With last year's tsunami-induced disaster at the Fukushima Daichi plant in Japan, Southern doesn't want its reactors to meet the same fate.

"We learned a lot from Fukushima, and all that has been taken into account," said Cheri Collins, general manager of Atlanta-based utility, one of the largest electricity distributors in the United States. "Our uncompromising focus is safety and quality."

During October's annual France-Atlanta 2012 conference, Collins explained how the newly designed Westinghouse AP1000 nuclear reactors at Plant Vogtle in Waynesboro, Georgia, will feature safety measures meant to prevent a Fukushima sequel.

They include the reactors' not needing electrical power to shut down safely and relying less on pumps and valves and more on natural heat.

Also, because of digital operation, a human controller won't be required for 72 hours, and the main core will remain cool because of a containment cooling system.

These design changes, Collins said, are meant to protect employees and the surrounding community in the event of a natural disaster.

Collins noted that while Southern keeps safety atop its list of priorities, it can't "control the weather," and it's hard to prepare for natural disasters such as the 2011 earthquake and tsunami in Japan or 2005's Hurricane Katrina on the Gulf Coast.

According to Mike Altizer, Southern's nuclear engineering programs manager, tests involving floods, earthquakes, fires and tsunamis were conducted in hopes of ensuring a natural disaster wouldn't affect the reactors.

Yet while Southern moves forward, last year's disaster has soured the prospects for nuclear energy in some European nations, while critics ask why more isn't being done to tap safer energy such as natural gas.

On March 11, 2011, a 9.0-magnitude earthquake, the fourth-largest on record, struck off the coast of Tohoku, Japan. It triggered a tsunami with 30-foot waves that later forced the shutdown of eight reactors at two plants in Fukushima.

The next day, a nuclear emergency was declared at the Daichi and Daini plants after the tsunami cut off electricity and disabled the backup generators at the former while causing the cooling systems to fail at the latter.

Roger Hannah, a Nuclear Regulatory Commission spokesman, said the agency is taking a number of actions in response to Fukushima. They involve equipment, training, procedures, maintenance and fire protection, he said.

"The Vogtle reactors are an advanced design that has more passive safety features," Hannah said. "The NRC does not allow a plant to operate if it does not meet the agency's stringent safety regulations."

According to the NRC website, on March 12, the commission passed regulatory requirements for nuclear plants in response to Fukushima. Those requirements include mitigation strategies to respond to extreme natural events that result in a loss of power at the plant, steps to ensure the safety and reliability of venting systems designed to release pressure and the enhancement of spent fuel pools.

Also, the NRC created the Japan Lessons Learned Project Directorate, a group that focuses exclusively on implementing regulations based on the lessons learned at Fukushima.

Edwin Lyman, a senior scientist for the watchdog Union of Concerned Scientists, isn't for or against the new reactors, he said, but he expressed concerns with the tests and safety features.

"In my judgment, the AP1000 design does not have any safety advantages compared to currently operating reactors and, in fact, may be less safe," Lyman said. "The features described are only designed to function in the event of [a] so-called 'design basis accident' -- not the type of severe accident that occurred at Fukushima."

At Fukushima, there was a total loss of power for nearly 10 days, so even if the reactors had been AP1000s, they would have run into trouble after 72 hours, Lyman said. In addition, the NRC has exempted the AP1000 from some of the modifications it is requiring at operating nuclear reactors after Fukushima, he added.

He said he isn't familiar with the NRC natural disaster tests, but "certain components of the AP1000 shield building were tested for their structural integrity under certain stress conditions and actually failed the tests, but the NRC discounted the results because it claimed that those components didn't need to pass those tests."

In a May 2011 New York Times report, NRC Chairman Gregory B. Jaczko said the shield building's design numbers seemed off. Jaczko, who stepped down as chairman in July, said the company had not tested the buildings under enough possible seismic activity situations.

However, the five-member NRC voted in favor of the licenses four to one, with Jaczko being the lone vote against it. Jaczko said he wouldn't speak on record to CNN, but he told CNNMoney on February 9 that the new licenses don't go far enough in requiring the builders to incorporate lessons learned from Fukushima.

Hannah explained there were many versions of the AP1000 design that raised questions among critics during its creation. The shield building was a major area of concern but was fixed before the final design was approved, he said.

A total of 19 changes have been submitted since the design began in 2002, the last of which came in June 2011, according to the NRC website.

Asked about Lyman's assertion that the Vogtle plants would incur problems if they went 10 days without power, as did the reactors at Fukushima, Hannah said all plants have some sort of backup generator that allows power to be generated in an emergency -- even one as big Fukushima.