A Massey University study in Taranaki is exploring the potential for solar farming co-existing with sheep grazing, providing two sources of income for farmers.
Led by Professors Danny Donaghy and Paul Kenyon from Massey’s School of Agriculture and Environment, the team will measure pasture composition, growth and quality around and under solar arrays.
“Solar farming in conjunction with sheep grazing is an exciting mixed system allowing farmers to obtain two income streams while ensuring the land area is still productive,” Professor Kenyon says.
The aim of the study is to provide data on pasture production and quality, which can then be used to model sheep carrying capacity or various sheep systems (i.e. a traditional ewe/lamb system versus an all year round lamb finishing system). Using this information, economic analysis can be undertaken to determine the income potential of both solar energy production and sheep productivity on a per hectare basis. It is envisaged that sheep are the likely animal of choice due to the potential for larger livestock to damage solar arrays.
“Due to the structure of the arrays, the amount of shading and light each area of land receives will differ each day and across seasons. Therefore, it is important that within a solar farm all these areas are measured across seasons to allow for a total picture of pasture production and therefore animal carrying capacity,” says Professor Kenyon.
There is also potential for shading, especially in the more humid periods of the year, to result in fungal growth and for potential health issues such as facial eczema to become an issue, so this will also be monitored. The shading may result in species compositional changes, with the potential for weed species to become prevalent, and even dominant. This is also being monitored, as the level of weed species will impact pasture production as well as quality, both which have an influence on sheep carrying capacity and performance.
Results from the study will be available in a year’s time. Massey received funding from the Agricultural and Marketing Research and Development Trust (AGMARDT).
Other solar farm projects
In September this year, news outlets reported that Todd Corporation is well advanced with plans to cover a 1022ha dairy farm southeast of Taupō with 900,000 solar panels, shipping container-sized inverters and a huge switchyard. All going to plan the solar farm will be fully operational by 2027, generating 400MW of electricity – enough power for around 100,000 homes.
Two solar farms are being discussed in the Wairarapa, and a $150 million-plus farm covering the equivalent on 262 rugby fields at Christchurch airport is scheduled to be generating 150MW – enough for 20 per cent of Christchurch homes – within 5-7 years.
New Zealand’s largest solar farm to date – a 5,800 panel facility generating enough electricity for 520 homes – is at Kapuni in Taranaki. It came on-line in May last year.