Salt of the earth…

Several of our last posts have focused on the economic and social responsibility legs of the triple bottom line.  With this post we return to the environmental leg, with a “green by definition” project which was just turned over for operation in sunny Spain.

“Green by definition” is one end of the Green Rainbow we talk about in our book.  These are projects which have as their main outcome an environmental improvement. The other end of the spectrum is “Green in General”, which would be, for example, release of your company’s payroll software.  Even those projects, we assert, can benefit from sustainability thinking.  But that’s not the topic of today’s post.  Today we talk about molten salt.

According to a great article in, “The 19.9-megawatt Gemasolar concentrating solar power plant uses 2,650 flat mirrors called heliostats arranged over 185 hectares of land to heat molten salt. The heliostats focus sunlight on a tower where liquid is heated up to 900 degrees centigrade. It is then stored for later use at above 500 degrees centigrade in tanks beneath the tower.”

Why salt?

Simple physics.  Salt retains heat longer than water.  Read about it at Sandia National Lab’s site.   Here’s a more detailed technical article about a plant to be built in Nevada.

And here’s a diagram of a molten salt solar power generation system.


The lesson for our project managers?  Learn the technology, the vocabulary.  Understand the importance and significance of such projects and be ready (and willing) to take on either a project like this.

Give yourself the opportunity to work on projects like this.