Off the grid solar solutions

Energy hungry mining companies are increasingly looking for off-grid power solutions, in an effort to reduce the use of diesel generators, bring down electricity costs and minimise carbon footprints.

Solar power solutions company Photon Energy told Australian Mining that solar power, particularly in remote locations is proving to be an attractive alternative which lowers electricity costs.

“Solar power is a clean, sustainable, and cost effective way to produce power and has a stable and calculable cash flow,” Photon Energy’s Australian managing director Michael Gartner said.

Gartner told Australian Mining that he is starting to see the emergence of an “industry-wide realisation” when it comes to managing energy consumption, costs, supply, and risks.

Most commonly diesel is used for remote electricity generation on mine sites, a practice that weighs heavily on the environment, health, bottom line and reputation.

A recent report from the World Health Organization says diesel fumes cause cancer.

The new ruling puts diesel fumes almost on par with second hand smoke.

And while the risk of cancer is fairly small a science panel said raising the status of diesel fumes to carcinogen from a 'probable carcinogen' was an important move.

This WHO finding may have significant repercussions throughout the mining industry, where workers are constantly exposed to high levels of diesel fumes, particularly underground miners.

It's on the same order of magnitude as passive smoking," Kurt Straif, director of the International Agency for Research on Cancer (IARC), said at the time.

"This could be another big push for countries to clean up exhaust from diesel engines."

Gartner explained that the cost of solar technology has in the last two years dropped significantly.

“Today solar is now the cheapest form of power at the point of consumption,” he said.

“This means self-consumption or avoiding the grid is now the most cost competitive way to provide solar power.”

Gartner said that in an off-grid situation the cost of diesel generation is significantly more expensive than electricity from a solar photovoltaic plant.

With the refinement of solar technology, it can now be seamlessly integrated into either a grid, off-grid or hybrid system delivering both power reliability and cost savings.

Discussing solar power reliability Gartner stated that the elimination of moving parts in a solar system means that in comparison to a diesel generator it requires less maintenance.

“When combined with diesel or gas generators in a hybrid system, solar helps reduces the total cost per kWh while the whole system takes care of a 24 hour power supply,” he said.

Solar power can also act as a booster for off grid power generation, run in parallel with gas or diesel generators to cover peak power requirements on site.

He explained that one of the company’s strengths is its ability to integrate demand management, so the site’s power system can be optimised; one example of optimisation is giving preference to solar throughout the day and diesel at night.

“We can just as easily integrate a solar PV plant with existing infrastructure and do a thorough analysis of the existing generation equipment, power demands and decide on how best to implement integration,” he said.

However the initial financial outlay for a mine to install an off-the-grid solar system is still proving to be a barrier, especially when it comes to existing operations.

“Financing is proving to be a significant barrier, especially for existing mines,” he said.

To combat this Gartner said Photon Energy has devised finance packages and power-purchase-agreement [PPA] solutions.

A PPA is an agreement between the power producer and the power consumer that sets all the conditions of the power supply agreement including price per kWh, the minimum kWh to be supplied and purchased, the quality of the supplied power, up-time and performance guarantees and what happens in the case that either party would not meet their obligations.

These solutions mean mining companies do not need to invest heavily in building a local photovoltaic plant, but can buy electricity on the basis of the power-purchase-agreement.

“We are aware that with any new technology customers will be cautious and to get over this barrier we are willing to put our money where our mouth is,” he said.

“The solar potential in Australia is huge, not harnessing it with today's technology is just pure wasteful.”

In 2011 Australian Mining reported Galaxy Resources received an award for its solar tracking panels at its Mt Cattlin lithium mine.

The miner won the Energy Generation and Distribution Award from the Sustainability Energy Association of Australia.

Mt Cattlin was the first mine in the country to have real time solar tracking panels installed to generate power on site.

By having solar tracking, the panels are able to follow the sun in all directions, providing 15 per cent more power than a single axis system.

Galaxy has 14 solar trackers and two wind turbines operating at the lithium mine, which create 226MWh per year of renewable energy and accounts for a sixth of the daily energy at the site.

The system was designed by Swan Energy.