But perhaps the most convincing evidence that solar is here and it's competitive is that oil companies are now using it to make oil extraction cheaper and cleaner.

Late last year news began coming out that the oil industry was turning to solar to help it pump crude.

Royal Dutch Shell (NYSE: RDS), Total (NYSE: TOT), the Kuwait State Oil Company, and Oman's sovereign wealth fund have teamed up to create a solar company called GlassPoint.

It is building a massive solar installation in the Oman desert to create steam to help pump oil. That one project will save more carbon than all electric cars sold so far by Tesla (NASDAQ: TSLA) and Toyota (NYSE: TM) combined.

What's more, using solar to help power an oilfield makes total economic sense. Up to 60% of the operating expenses at heavy oil fields are for fuel purchases.

So at a time when oil companies are cutting costs — curtailing exploration and laying off tens of thousands of workers — they are still interested in spending for projects that can reduce costs.

And that means solar.

Petroleum Development Oman, which is partly backing GlassPoint, accounts for 70% of the nation's oil production and 100% of its gas supply.

It is highly indicative that it is turning to solar to complement its fossil fuel operations.

This is only going to continue through 2030, as solar continues its march toward becoming the world's dominant source of electricity.

As that happens, the companies that improve solar technology and reduce its costs are going to be the biggest winners for investors.

David Fuller's view

Here is a PDF of the Outsider Club article. 

Fuller Treacy Money has long maintained that solar power would dominate not only renewable energy but also prove to be more successful than any fossil fuel, due to its unique advantages.

Moreover, solar power is limited only by our imagination.  We have often seen large concentrations of solar panels which are ideal for low populated desert regions of our planet.  However, smaller solar units are increasingly prevalent for use on buildings, first rooftops but also on siding and even windows.  With the development of graphene and special paints, the ability to capture sunlight will soon be on moving vehicles, not least trucks and automobiles. It will not be long before we are wearing solar clothing, to keep us warm and to charge our phones or any other small instruments which we carry.     

The only point I disagree with in this section of the article reproduced above is the concluding comment that solar companies “are going to be the biggest winners for investors.”  A few may but with all new technologies there are many participating firms but few survivors. We have already seen some of this with the solar industry.  I would rather own some of the companies which benefit most from cheaper energy prices, especially when they capture investor interest and start to outperform.