Atlassian co-founder Mike Cannon-Brookes’ $40bn SunCable hit by executive departures and redundancies

The tech billionaire’s ambitious Sun Cable renewable project has been hit by a string of executive exits, adding to uncertainty over the development.

Staff have left or been made redundant at Mike Cannon-Brookes’ SunCable.

Billionaire Mike Cannon-Brookes’ $40bn SunCable has been hit by a string of executive departures and redundancies, amid growing concerns a $100m fundraising round for the ambitious renewable project has attracted only tepid investor interest.

The Australian has confirmed several top level executives have left the business in recent weeks, and sources said close to one-third of SunCable’s Darwin office have recently been made redundant. Among those that have left the business owned by Mr Cannon-Brookes, the high-profile Atlassian co-founder and renewable energy evangelist, include SunCable managing director Cameron Garnsworthy and chief development officer Martin Hay.

Both were appointed in January last year, with Mr Garnsworthy having two decades of experience in the development, construction, and operation of more than 30 solar, wind and battery projects in Australia and Europe. He joined the State Electricity Commission of Victoria board last year.

Mr Hay was previously in executive roles at companies such as Worley, UGL, GHD and KBR. Both their LinkedIn profiles show they have now left SunCable.

SunCable said on Monday there has been a number of staffing changes in the last 12 months, including the hiring of a CEO, project director and several roles being actively recruited.

“There have also been changes to the structure that better align the organisation to deliver the next stage of development,” a spokeswoman said. “We are unable to make comment on individual employee circumstances.”

Martin Hay and Cameron Garnsworthy have both recently left SunCable

The SunCable departures follow Mr Cannon-Brookes last week losing two top executives from his private investment company, Grok Ventures.

Grok’s chief executive Tan Kueh and chief investment officer Jeremy Kwong-Law have moved on, with Mr Cannon-Brookes’ climate investments now being led by Casey Taylor, the chief executive of his family office, Cannon-Brookes Collective. She will also oversee philanthropic arm Boundless Earth led by Eytan Lenko.

One of SunCable’s longest service employees, ex-head of project development Joe Sheridan, also recently exited along with head of government affairs Andrew Treble and several others in government, industry advisory and community engagement roles.

Ms Kueh was appointed as Grok boss in January 2024, and had approached wealthy US families and prospective financiers for Sun Cable investment in July 2024.

A map showing SunCable’s plans for a pipeline to Singapore.

A formal pitch delivered to Australian investors in the last three months has failed to secure funding to date in its maiden $US100m ($154m) capital raising, fuelling doubts that the billionaire is capable of delivering one of the world’s largest renewable energy projects.

SunCable has denied the fundraising was behind schedule, claiming “discussions are advanced with a couple of parties” to stump up at least part of the funding. The capital raise is going well, and we have had strong interest from multiple investors,” SunCable previously told The Australian.

Ms Kueh’s appointment last year saw Mr Kwong-Law, himself a former Grok chief executive, moved to chief investment officer amid a change in strategy to focus on climate financing and accepting third-party funding to turbocharge action on climate.

Grok said both executives had “played a huge role in Grok’s journey and our mission to decarbonise the planet” and that the management changes “will help us move with more speed and impact. The climate challenge isn’t slowing down, and neither are we.

“Grok remains committed to making bold investments that push us towards a better tomorrow.”

The Suncable generation site in the NT

Mr Cannon-Brookes has pumped about $7.8m into SunCable Holdings Pty Ltd in three transactions over the past four months, according to filings with the corporate regulator. His Grok is the majority owner of the privately held company, documents show, with an entity controlled by Xero founder Craig Winkler the only other shareholder with a minority stake.

In its first iteration, SunCable planned to deliver 900MW of green power to industrial customers in Darwin. The project also aims to supply 1.75GW of electricity to Singapore by an undersea cable. At 4200km, the cable to Singapore would be more than five times bigger than the longest submarine link yet proposed – the 767km Viking link between Britain and Denmark – testing engineering capabilities and exposing the project to sovereign risk as it flows near Indonesian territorial waters.