NEW YORK (TheStreet) -- Several years ago I wrote a couple of articles for TheStreet that were negatively slanted toward investing in solar stocks. I called them a fad. To preface this update, it would be great if things like solar panels on every roof or turning uninhabited desert in Arizona and Nevada into solar farms made economic sense, but for now they don't.

There have been two types of obstacles that have existed for this group and for now there are no signs of improvement.

The first is the extent to which solar companies have relied on tax credits or other forms of subsidy for their customers to buy and install the product. This is not just a U.S. phenomenon but is also the case in Germany, as evidenced by that country's large weighting in the

Guggenheim Solar Energy ETF

(TAN) - Get Report

and the

Market Vectors Solar







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Subsidies have played a huge role, but Germany and Spain have both been reducing these subsidies, threatening the future viability of the industry. This has not been an issue in the U.S. yet, but given the state of financial affairs in the U.S. it would not be a shock to see subsidies cut. That would certainly be another nail in the coffin of the industry.

The other element has been how solar stocks and the ETFs have tended to trade. Before this year the correlation to oil stocks was very high. The logic was that as the price of oil goes up it generally benefits the oil companies but also creates more perceived need for solar products. When oil prices went down it generally hurt oil companies but created less urgency for solar products.

This year that dynamic seems to have changed as the

Energy Sector SPDR

(XLE) - Get Report

, which is a broad proxy for the energy sector is essentially unchanged for the year while the TAN and KWT ETFs are each down about 50% this year. I believe this year's performance is attributable to the subsidy issue and what that might mean for the entire industry.

This past week

First Solar

(FSLR) - Get Report

, one of the big players in the space, came out with earnings and guidance and was met with brokerage firm downgrades. This past weekend


noted that First Solar "conceded that the strategy that it and other solar companies have been following is broken and that deep changes must be made to salvage the promise of renewable energy."

Another fundamental threat to the industry comes from Chinese solar companies and accusations that they are creating a supply glut which is hurting all competitors -- including Chinese companies themselves as most of those stocks are down 60% for the year, faring worse than the ETFs.

There could always be a "back from the dead" trade on these names and I would expect them to rally should the price of crude oil put in a repeat of 2008 when it went to almost $150 per barrel. The conflict here is investing with the heart vs. logical investing. A lot has to go right for these stocks to achieve the potential perceived in 2008 and that seems very unlikely.

At the time of publication, Nusbaum was long XXX, although positions may change at any time.

Roger Nusbaum is a portfolio manager with Your Source Financial of Phoenix, and the author of Random Roger's Big Picture Blog. Under no circumstances does the information in this column represent a recommendation to buy or sell stocks. Nusbaum appreciates your feedback;

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