It's been nearly nine months since an earthquake and subsequent tsunami in Japan turned the fortunes of the nuclear world on its head. A nuclear renaissance in the U.S. came to a halt, Germany decided to nix its nuclear plants, and the industry hasn't been the same.

But there are three remaining reasons that I don't think nuclear is a place investors should be looking for value right now.

For safety's sake
Whether it's mechanical failure, human error, or a natural disaster, there are major risks associated with nuclear plants. Boosters may count these as one-time events, but they've happened more than once, and with Japan looking at billions of dollars to rebuild what was lost after the Fukushima Daiichi disaster, the risk should be a major factor in any investment.

Costs are rising, not falling
The cost per watt of nuclear energy is lower than that of many other energy sources, but the costs are heading in the wrong direction. When NRG Energy (NYSE: NRG) nixed its planned nuclear expansion, rapidly rising cost estimates were a major factor. Estimates tripled in the planning stage, making the power that would be delivered less cost effective.

Nuclear also benefits from a variety of government subsidies including limited liability, without which nuclear would be nearly impossible to build. And NRG was counting on a government loan guarantee to complete its plant. Compared to other alternative energy sources like wind and solar, whose costs are falling, nuclear is headed in the wrong direction.

It's a dying business
A look at how financial markets view nuclear power may give even the most hardened supporters pause. Rating agencies have downgraded companies with nuclear assets, and nuclear stocks have plummeted this year.

Investors should also consider that in the past year, U.S. nuclear power generation was down 2.7% and worldwide capacity has fallen from 375.5 GW to 365.5 GW. It's true that nuclear is out of favor, and according to trends, renewable energy is picking up the slack.

Foolish bottom line
Despite backlash from commenters when I asked if nuclear was really safe, it turned out it hasn't been for investors since Japan's disaster. There hasn't been a bounce back, and shares of Cameco (NYSE: CCJ), Uranium Energy (NYSE: UEC), and Uranerz Energy (NYSE: URZ) have continued to slide.

Considering the trends away from nuclear in many locations worldwide, I don't see this business getting brighter any time soon. Disagree? Leave your thoughts in the comments section below.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.