Let the sunshine in

Solar is the power solution of choice for two Farmlands shareholders – free-range chicken farmers in the Waikato and an agricultural contracting family on the West Coast.

Renewable at Hart

“Here chick, chick, chick” is heard frequently at Murray and Margaret Hart’s property where they grow free-range chickens for Ingham’s, to be sold under the Waitoa Free Range brand. Since 2013, solar power has kept their chickens comfortable and well-looked after.

Now operating under the Tatua Free Range Limited Partnership, Murray and Margaret work with partners Lucas and Clarissa Arnold on 18ha in Tatuanui, near Morrinsville in the Waikato. The Harts’ have been growing chickens for over 34 years.

Four state-of-the-art chicken sheds run through the middle of the property with maize fields making up the difference. Recent free-range development has allowed the chickens more access outside of the sheds, giving the young chickens more space to range as they mature.

“We were wondering about wind generation but then we came across Meridian’s stand at Fieldays. They were promoting solar power for dairy farmers but the more we investigated, the more solar power just seemed like common sense for us as well,” Margaret says.

It was important for the Harts’ that solar power would be able to work seamlessly alongside their generator, which is an animal welfare regulation on chicken farms – ventilation in the sheds must be maintained at all times for the chicken’s comfort. This can be an issue if you have a power outage so the ability to switch between solar and generator was a priority. Luckily, with assessment from Meridian, one of the existing chicken sheds was deemed to be in a premium position to absorb the sunlight and was close enough to the generator room to have two 10 KVA inverters also placed within the room.

The inverters convert the solar energy to electricity and are set up to utilise as much energy as possible on site. If any energy is not used, it is exported to the power grid.

“The one problem is that dirt can decrease the productivity of the panels but every year, around the same time as Fieldays, you just give them a brush and wash off the dirt and that’s it!”

As with any new development, the initial set-up cost was a factor but as the years have gone on, the benefits have paid for themselves.

“For chickens to be comfortable, they need to be the right temperature, so the power used for feeding, lighting and ventilating the sheds can be very expensive. Solar has reduced the energy cost significantly.

“The panels take a minimal amount of sunlight and work well for chickens in particular. The draw on the power is relative to the amount of ventilation the chickens require. In the summer you need more fanning but have more daylight hours. The chickens sleep at night, so there are no feeders or lights running, drawing less power. In the winter, the chickens don’t need as much fanning which corresponds well with less daylight hours,” Margaret says.

It has been a logical move for the Tatua Free Range Partnership. “I believe that if we don’t have sun, we don’t have life, so it makes sense. If you can get the curve right and do your work during daylight hours, it can work very well.”

Living off-grid

When the cost of connecting standard grid power to their new home looked like it was going to substantially dent their bank balance, Bevan and Caroline Langford
decided renewable energy was the solution.

The pair sold their 60ha dairy farm 5 years ago, moving their agricultural contracting business and setting up a beef and dairy grazing farm on a 27ha block in Karamea on the West Coast. There, Bevan and Caroline were faced with the nasty realisation that connecting their new build to power lines over half a kilometre away was going to cost upwards of $100,000. So, they began looking at other power options. Solar energy ticked the boxes and ultimately became the foundation on which their new home was designed on.

The house is positioned to capture the best sun angles during both winter and summer and, with a large glass frontage and tiles on the floor, to capture the heat.

“The system was designed by Independent Power Auckland and is based on power usage. The house is 200m2 including the garage and we bought appliances that have low energy usage. We use LED lights but chose to heat our water with gas and wetback rather than tax the solar. We also have an underfloor heating system that runs off the wetback from the coal range. The water runs through a manifold and we can control the heat in each room,” Bevan notes.

The house, which took approximately 6 months to build, is unique in that the solar panels are not situated on the roof.

“We chose a fixed panel frame on the ground. It’s set on our back lawn at 22 degrees east which puts it at the premium angle to get best use of the sun during winter. The house was actually designed to have the panels on the roof, but realistically I couldn’t see myself getting up there for the maintenance, so they are more convenient and safer on the ground,” Bevan says.

As part of Bevan’s contracting business, a large workshop is used to maintain and service his machinery – only 150m from the house, it can also support the solar energy. “The workshop has a 20KVA diesel generator to run the welders and grinders but can also provide backup power to the house as needed,” Bevan says.

The power usage determines the solar system size, so while Bevan and Caroline could have made do with 11 of the 250w panels, the added power of 15 panels was too good to pass up. With 48v running through two inverters, on a good summer day the panels will produce 17kW of power per day, which produces enough power to charge 24 2v/1,000 amp batteries.

A controller monitors how much power is coming in, power usage, the state of batteries and automatically starts the workshop generator to support the system when power usage gets high or the battery state drops below 70 percent.

All up, the system cost $50,000, half the amount a standard power connection would have cost. Each battery has a 25-year lifespan so Bevan is confident that the whole system will have paid for itself in energy savings before this time.

“The main thing we learnt was to look at what appliances we were running in our house. The solar energy system we have was built around how much energy we use, so it can be built to suit budgets – it just depends on your usage,” he says.

Discover renewable energy suppliers such as Meridian Energy, at www.meridianenergy.co.nz