Here are some studies comparing solar and diesel irrigation.
The non-profit agency Solar Electric Light Fund did a study in 2008, entitled “A Cost and Reliability Comparison Between Solar and Diesel Powered Pumps.”
The study opens with this:
“There are very distinct differences between the two power sources in terms of cost and reliability.
Diesel pumps are typically characterized by a lower first cost
but a very high operation and maintenance cost. Solar is the opposite, with a higher first cost but very low ongoing operation and maintenance costs.
In terms of reliability, it is much easier (and cheaper) to keep a solar-powered system going than it is a diesel engine. This is evident
in field where diesel engines lie rusting and unused by the thousands and for years without anyone touching them.”
The paper cites another study sponsored by the Government of Namibia,and the United Nations Development Program.
The Namibian report furnishes overwhelming evidence that for small to medium sized wells, solar (PVP, or photovoltaic pump) is much cheaper on a life cycle cost basis than diesel-powered (DP) pumps.
When looking beyond the original purchase price, PVP pumping systems cost anywhere from 22-56% of what diesel pumps cost and can achieve a payback over DPs in as little as 2 years.
For a copy of the report, click here:
A recent Stanford University study by Jennifer Burney et al captured quite a lot of attention. The study was based in Benin and was entitled “Solar-Powered Drip Irrigation Enhances Food Security in the Sudano-Sahel.”
link to full text :
and a short video about the project