As a German, I live in a country that prides itself in its abandonment of nuclear energy. Personally, I consider this a tragedy. Hearing that elsewhere new reactors are planned is good news. Before you flame me (or stop reading), please hear me out.
First, I acknowledge that nuclear energy has a problem - Fukoshima demonstrated that. But I would argue that the problem has less to do with technology, but with regulation. With proper regulation, and above all transparency and supervision from independent bodies, nuclear energy promises to be a safe, economic and environmentally friendly technology.
So let me dismantle the arguments against nuclear energy:
Safety: The truth is, nuclear energy is safer than everything else we have. The estimates from the death toll from Chernobyl ranges from 5,000 - 200,000. My guess is that both numbers push agendas. Either way, this picture puts death by oil, coal and nuclear into perspective. But as it does not cite clear numbers, let me throw in that 24,000 deaths every year are caused by coal-fired power plants in the USA alone! This is just the US (Think how high the number probably is in China and India), and does not include deaths through mining. Do the math yourself.
Waste: Storing nuclear waste is a huge problem. Less known is the fact, that many of today's aging reactors were designed to produce material for nuclear weapons as a byproduct, but also large amount of waste. There are several promising designs that produce significantly less waste. Not only that, there are also ideas for "cooking" the waste (Pyroprocessing), which could get rid of radioactivity in as little as 100 years while generating energy. But more research is needed here.
So, what's to be done?
Regulation: Here I see the biggest problem. The energy industry ruined the reputation of nuclear power by practicing secrecy and obstruction for decades. Japan's TEPCO is notorious for this, but I'd argue that Europe's Vattenfall is not much better. Compare this to the aviation industry: The low fatality rate is impressive, inspite of a technology where failure can easily lead to hundreds of deaths. But if something happens, the incident is analyzed and published with merciless rigor. We need the same oversight, rigor and transparency in the energy sector.
Technology: There are many promising reactor designs that could be safer, produce less waste and use cheapter fuel, like Molten salt breeders. Other designs include PRISM and IFR designs in general. Some of these are specifically designed to close the nuclear fuel cycle. While this does not remove the existing waste, they promise not to increase the waste problem.
I consider it madness to abandon this technology, rather than to try to tame it. I applaud Bill Gates for investing in nuclear technology. We have a serious energy problem on this planet, and nuclear power can be a part of the solution. Everybody is talking about the environment. Nuclear power has the potential to help.