SolarReserve employs molten salt as a kind of cheap and highly efficient battery, overcoming some of the traditional limitations of large-scale electrical generation. Traditionally, one of the criticisms of solar power and other renewables involved the inability to provide consistent energy since the wind does not always blow and the sun does not always shine. SolarReserve overcomes this problem with an ingenious and scientifically proven method.
Solar power is generated in one of two ways primarily. The method most familiar is the photovoltaic cell, which directly converts sunlight into electricity. However, photovoltaic cells are still relatively expensive and inefficient converters of energy. As a result, they will need significant refinement before they can offer electricity at competitive prices when compared to fossil fuels electrical generation.
On the other hand, heliostatic power plants use a computer-controlled array of mirrors to focus concentrated sunlight onto a central point. This concentrated energy is converted into heat, which then generates steam and turns a traditional electricity-generating turbine. Yet, heliostatic plants still suffer from the problem of storage as they cannot generate electricity when the sun is not shining. Also for the scale needed for these power plants, lithium ion batteries are very expensive and inefficient.
SolarReserve’s molten salt overcomes this limitation in an ingenious way. The battery used is a mixture of potassium nitrate, which is a common fertilizer, and regular sodium-based salts. It holds heat incredibly well with a waste level of just one or two percent. The salt battery operates at temperatures above 1000 degrees Fahrenheit and slowly releases heat energy, which in turn creates high intensity steam to turn a generator.
As such, SolarReserve’s plant will operate around the clock and offer something in the neighborhood of 15 hours of storage capacity. This means it can work at night and for days on end when the sun is shining at less than full capacity. SolarReserve’s plant can thus power a large number of homes reliably and with zero environmental impact. No additional power sources are needed to supplement the plant.
Once operational, the plant will generate between 100 and 600 megawatts of electricity, which will power between 100,000 and 600,000 homes. This could allow sunny desert states like Nevada to become major energy exporters, building jobs and supporting the economy while also decreasing greenhouse gases.