Maxol said it intends to spend an additional €100m (£85.8m) by 2020 expanding and enhancing its network.
The investment in the chain comes after it spent €128m (£110m) between 2012 and 2017 on capital investment. There are 231 Maxol service stations in Ireland, with 115 of those owned by the company. It aims to have more than 120 company-owned sites by 2020. It currently has 14 sites at various stages of the planning process.
Mr Donaldson said Maxol's profits rose by about 15% last year to roughly €15m (£12.9m), but declined to give a specific figure as the latest set of accounts have not been signed off.
He also said that the group continues to be mindful of the continuing increase in electric and hybrid vehicles, which is a longer-term challenge facing the industry. Maxol generates about 60% of its profits from fuel and 40% from food and other items.