ABB delivers microgrid power for remote WA towns

Remote locations such as Marble Bar and Nullagine in Western Australia — towns which are not connected to the grid — would typically rely solely on diesel fuel for their power. Instead, a microgrid solution from ABB is enabling multiple energy sources, maximising the intake of solar power generation and minimising diesel fuel generation.

Marble Bar is a town and rock formation in the Pilbara region of north-western Australia. It was named after a local deposit of mineral first thought to be marble but which later proved to be jasper. Officially gazetted in 1893 following the discovery of gold in the area, the town once boasted a population of 5000 people when the prospectors came in their droves. The gold rush in the Pilbara was short-lived, however, with the huge discoveries on the Eastern Goldfields and in The Murchison at places like Coolgardie and Kalgoorlie. In 2006, the population was less than 200.

On the way to Marble Bar, a road sign offers visitors the ‘warmest welcome from Australia’s hottest town’. The arid climate and blistering summers helped this small mining centre in remote Western Australia set a world record for heat — 160 consecutive days at 37.8°C or above, ending on 20 April 1924 — which still stands after 90 years! During December and January, temperatures in excess of 45°C are common, and the average maximum temperature exceeds normal human body temperature for six months each year. Rainfall mostly occurs in the summer months, and Marble Bar receives 159.6 clear days annually.

The burning sun has also made Marble Bar unique as the site of one of the world’s first utility-scale, high-penetration solar photovoltaic diesel power stations. The other station is located in the adjoining gold-rush town of Nullagine, with a similar history and now home to 200 people.

ABB, through its Darwin-based team, worked closely with Horizon Power and SunPower Australia to install these new power stations, which are setting benchmarks – at an 85% peak – for isolated hybrid diesel power systems with extremely high renewable energy generation and conversion.

The Marble Bar and Nullagine power stations each consist of four 320 kW diesel generators and a 300 kW solar array. They utilise some 2000 solar modules and a single-axis solar tracking system, which follows the path of the sun throughout the day. The ground-mounted systems were the largest solar tracking systems commissioned in Australia at the time.

The hybrid solution includes a photovoltaic and a diesel generation plant as well as integration and control solutions. The microgrid is equipped with ABB’s PowerStore kinetic flywheel grid stabilising technology, which enables high solar energy penetration by injecting or absorbing power extremely fast in order to stabilise fluctuating power output from the solar power plant. ABB’s Microgrid Plus technology will help control the network.

The hybrid microgrid power solution is now supplying both towns with close to 60% of their power through solar generation, saving approximately 400,000 L of diesel fuel and 1100 tonnes of greenhouse gas emissions each year.

The ability to resolve intermittency issues caused by solar and wind generation in weak power systems enables renewable generation to be increasingly used as a primary power source in many remote communities with zero or limited access to diesel or other types of fossil fuels. About 80 similar ABB installations in a wide variety of applications around the world utilise this powerful green technology, showing that freedom from fossil fuels is a real option now and in the future.