Green energy for tower power

BAI aims to see 20-30% of its transmitting facilities becoming solar powered.

As reported in Critical Comms last year, BAI’s Muswellbrook broadcast tower has turned its back on traditional mains power, going off-grid to run entirely on solar thanks to the introduction of advanced battery storage technology.

BAI is the owner and operator of one of the most extensive terrestrial broadcast transmission networks in the world. In Australia, the company provides fully managed transmission services, site sharing, co-hosting, online application hosting and infrastructure services to the telecommunications, emergency services and broadcasting industries.

BAI also owns businesses in Hong Kong, Canada and the US that specialise in the design, installation and operation of cellular and Wi-Fi coverage in mass transit subway venues.

Photon Energy designed and delivered the Muswellbrook solar power project in association with (the German Energy Agency) Deutsche Energie-Agentur GmbH (dena) using predominantly German technology.

Primarily used for local radio broadcast, the Muswellbrook tower is also relied on by local emergency services for communications during bushfires and floods.

“We’re thrilled to be involved in this groundbreaking project. As a service provider that relies heavily on external market forces, it’s exciting to think that soon we’ll be able to generate much of our own power,” said BAI Group Chief Executive Officer Jim Hassell.

“The longer-term outcome of this project will prove beneficial for our customers in many ways, as we’ll be able to provide them with a lower carbon footprint, more cost certainty and improved reliability against the grid in remote locations.

“We’re looking forward to assessing the outcomes of this project for a potential future network-wide implementation,” Hassell added.

New South Wales Parliamentary Secretary for the Environment, Leslie Williams MP, attended the system launch on 7 November 2014.

The solar power system is a 39 kWp solar power installation using 216 kWh of batteries and a 8 kVA diesel back-up system for emergencies. The technology comprises: 156 Q CELLS Q-PRO G3 255 Wp solar panels, 72 BAE Secura PVV 2 V 1500 Ah batteries (supplied by R+J batteries), three SMA 8.0H Sunny Island inverters and a Photon Energy 24/7 monitoring system.

“The high quality of the German-engineered technology provides the reliability required in remote areas. BAI is excited to be at the forefront of integrating this advanced technology into the communications sector,” said Hassell.

The road ahead is green

To get some more information about BAI’s power plans, we spoke with Adam Fricker, general manager network strategy and planning.

CC: Looking at your whole transmitter/receiver facilities network, can you give a breakdown of how many are mains powered and how many are solar or some other form of energy?

AF: BAI has embarked on a journey that we hope will inevitably see 20-30% of its facilities transmitting using solar power. Our initial investigations began with our hybrid wind and solar site at Mount Owen in Tasmania. This has progressed with our first solar and storage facility in Muswellbrook, New South Wales.

CC: Do your customers ever ask you about renewable energy?

AF: Our customers are focused on sustainable methods of delivering their business over the long term. There are natural synergies between the investment in renewable energy and storage and the cost certainty this provides to the operations of communications infrastructure. BAI is committed to providing options that meet the varying needs of our customers, for example, reliability and cost savings. We have had a number of enquiries about the Muswellbrook project and there is growing enthusiasm for this solution to be used on a wider scale.

CC: Is the Muswellbrook installation considered a trial or a fully fledged system?

AF: It is considered a prototype that will remain fully operational over the next decade and beyond. The lessons from this prototype are being used to inform our network-wide design for further rollout.

CC: What is the back-up power plan for Muswellbrook?

AF: Due to the criticality of the services provided by our site infrastructure, we have to design for high levels of availability. Given the infrequency of long periods of low solar generation, it is more efficient to provide this support via a standby diesel generator than via purely solar and storage. We envisage minimal reliance on the generator. While we are proving this concept, the mains supply is still available and we foresee disconnecting the mains connection after 12 months.

CC: Have you noticed any operational expenditure savings so far?

AF: Since the Muswellbrook site has been live, it has been working on the solar system 100%. There has been no need for diesel or mains supply. This has resulted in a significant reduction in our retail electricity expenditure to date.

CC: What are the plans for installing more solar power systems?

AF: We are currently in the lessons learned process and are refining the network-wide design. We are also in consultation to develop a plan for installation at another 50 sites across Australia.

CC: Are there any locations where solar might not be appropriate due to crowding or space limitations?

AF: Not all of our sites are positioned in suitable locations for solar power. The wind generation component at our Mount Owen site is one identified alternative when 100% solar is not feasible at a site. However, in urban locations with high power requirements of broadcasting, renewable energy is unlikely to be a viable option.

************

• The photovoltaic array produces enough solar energy to power 7.3 average Australian households for a year.
• The 216 kWh of batteries can store enough energy to run the Muswellbrook antenna for up to 43 hours or enough energy for an electric passenger car to drive from Sydney to Melbourne and back.
• If all chargers run at 100%, the batteries will fully charge in five hours and 32 minutes.