Brisbane at night

Executive leadership team

Andrew Bills 

andrew bills

Chief Executive Officer

Andrew Bills commenced as CS Energy’s Chief Executive Officer in October 2018. He has more than 20 years’ experience in the energy and infrastructure industry where he has worked in trading, retail, generation, LPG, solar, and renewables. 

Prior to joining CS Energy, Andrew worked for Origin Energy for nearly a decade in multiple roles with his last as General Manager LPG and Health, Safety and Environment in the Energy Markets Division. In this role Andrew led the LPG arm of the business, a complex task managing the entire supply chain that spans across 75 sites in nine countries, including four joint ventures in the Asia Pacific.

Prior to Origin, Andrew worked at Babcock & Brown Power where he was responsible for managing commercial operations undertaking several acquisitions and managing joint ventures. Before that he was a senior executive at Stanwell Corporation where he managed the trading and marketing functions.

Andrew has served as a director on multiple boards, including as Chairman of Gas Energy Australia, and an Industry Representative on the Advisory Council to the Energy and Water Ombudsman Queensland. He is currently a director on the board of the Australian Energy Council.


Leigh Amos 

leigh amos

Executive General Manager Plant Operations
BEngTech, MBA

Leigh Amos joined CS Energy as Executive General Manager Plant Operations in 2019. In this role he manages the operational performance of CS Energy’s generation assets, as well as the environment, and health and safety functions.

Leigh has built an impressive track record as a collaborative and effective leader managing complex and geographically diverse operations in the energy industry both in Australia and overseas. 

He has a nuanced understanding of the challenges facing the energy industry and has a real passion for empowering people to build a constructive culture.

Prior to joining CS Energy, Leigh fulfilled a variety of roles at Western Australian energy company Synergy across their coal, gas and renewable assets. Before that, he worked for the NZX listed Contact Energy managing their gas-fired assets in Auckland, Hamilton and Napier, as well as the Oakey Power Station in southern Queensland.

Leigh began his career in the energy industry as an I&C Technician at Callide Power Station in 1997.


Darren Busine 

darren busine

Executive General Manager Technology, Markets and Commercial

Darren Busine has more than 25 years’ experience in senior finance roles in the energy and banking sectors. At CS Energy he is responsible for the trading and analytics, strategy and planning, technology, resources and commercial, and procurement functions.

Darren joined CS Energy in 2016 as Chief Financial Officer. In 2017 we was appointed as Executive General Manager Revenue Strategy and in 2021 he was appointed to his current role.

Prior to joining CS Energy, Darren was CFO at QEnergy, an energy retailer based in Queensland but targeting the small to medium size business market across the eastern seaboard of Australia. Darren was the CFO of Energex from 2007 to 2014. During this time Darren led the finance, legal, company secretariat, and risk and governance teams. Joining Energex after the sale of their retail operations, Darren played a key role in the transformation of the Energex business, including implementing significant improvements to financial management and reporting.

From 2000 to 2007 Darren was with Ergon Energy, initially as Group Finance Manager and then CFO from 2006. Darren was responsible for integrating the finance functions of newly merged distribution entities. He also undertook improvement roles, including the setup of joint venture operations for billing and IT services with Energex.

Prior to his experience in the energy industry, Darren spent 10 years with Suncorp. Darren is a director of the Queensland Music Festival where he serves as Treasurer. 


Emma Roberts 

emma roberts

Executive General Manager Future Energy
LLB (Hons), BAppSc (Ecology)

Emma Roberts leads CS Energy’s Future Energy division, which is spearheading the development of a new low-cost, decarbonised and flexible energy portfolio for the business. The division includes business development, future energy asset design and project management, retail sales, customer products, and policy and regulatory advocacy.

Her in-depth knowledge of the National Electricity Market, coupled with her commercial acumen and leadership skills, has seen Emma hold a variety of senior roles since joining CS Energy in 2012. These include Senior Legal Counsel, Acting Executive General Counsel and Company Secretary, and Head of Future Energy.

Emma has developed a strong reputation for leading cross-functional teams to deliver positive business outcomes. She led the establishment of CS Energy’s retail function and has driven CS Energy’s pivot towards a customer-focussed culture as the business diversifies in response to the transformation of the energy system.

Emma holds degrees in law and applied science. Prior to joining CS Energy, she was a senior associate at McCullough Robertson Lawyers for eight years, working in the corporate and intellectual property teams.


Andrew Varvari

Andrew Varvari

Chief Financial Officer 
LLB, B-Bus, G Dip App Fin (Sec Inst), F Fin, Grad ICSA, GAICD

Andrew Varvari leads CS Energy’s key corporate functions of finance; energy and financial risk; people and culture; corporate affairs; legal; risk, compliance and assurance; and Board secretariat. As an experienced energy and resources executive with over 15 years in the industry, and 15 in executive leadership roles, Andrew focuses on safely delivering high value business outcomes.

Andrew joined CS Energy in 2012 and has performed a variety of executive roles, including Executive General Counsel and Company Secretary, Acting Chief Financial Officer, and the role of Executive General Manager People & Safety until 2017, when his responsibilities were expanded to include additional corporate functions to leverage greater alignment and cross functional working relationships, providing strategic counsel, advice and support across CS Energy’s portfolio.

Prior to joining CS Energy, Andrew led BG Group plc’s legal function in Australia, which included responsibility for QGC’s Legal, Secretariat, Business Services and IT functions. Between 2007-2012, Andrew played a key role in the development of Shell’s upstream and midstream businesses as part of its Executive Leadership Team, including the integration of the existing Queensland Gas Company and BG Australia businesses following the 2008 takeover of QGC by BG Group plc, and the development and construction of the $20 billion Queensland Curtis LNG project.

Andrew’s experience also includes five years in legal and executive roles at Stanwell Corporation and seven years in private legal practice.