Water is a precious commodity in the US state of California. However, it is very unevenly distributed. Because a large part of the rainfall takes place in northern California. Consumption, on the other hand, is mainly concentrated in the south of the state. Over time, a widespread system of irrigation canals has emerged, transporting the water to where it is needed. Some time ago, researchers proposed building solar panels over each of these channels. The potential of this approach is enormous: if the entire sewage network – more than 6,000 kilometers long – were set up for it, 13 gigawatts of green electricity could be produced. From a purely mathematical point of view, this would be sufficient to supply renewable electricity to 9.75 million of California’s 13.1 million households. The approach is now being field tested for the first time as part of a $20 million project.
In addition to electricity production, there are 3 other advantages:
On the one hand, it must be checked whether the desired amounts of green electricity can actually be generated. At the same time, a number of other potential benefits can also be explored. These include, for example:
1. Less Evaporation: It is estimated that between one and two percent of the water has so far been lost through evaporation. This roughly corresponds to the private water consumption of approximately two million inhabitants. The amount can be significantly reduced by the shaded solar panels.
2. Better Water Quality: The sun’s rays not only provide evaporation but also stimulate plant growth. This partly undesired effect could in any case be mitigated by the solar panels installed above the water.
3. Less maintenance work: Fewer plants would not only improve water quality but could also reduce the need for human intervention. This would reduce the cost of the overall system.
Until now, however, these advantages only exist in theory. Now they need to be verified in reality for the first time.
The use of space is kept to a minimum
The first associated solar panels will be installed this fall. The pilot project is expected to be completed in 2024. Ideally, sufficient data will then be available to decide whether a large-scale expansion is worthwhile. In principle, the approach also has the advantage that no new areas are needed. This is not an insignificant point in a densely populated state like California. A similar approach is therefore pursued with the so-called agri-photovoltaics. However, there are no irrigation channels here, but arable land with solar panels. California is also by far the US state with the strongest economy. The power requirement is correspondingly high. It is therefore logical to generate green energy on-site to simplify transport.