Stephen Grant of Grant Engineering was named industry entrepreneur of the year.
"I never in my wildest dreams thought that we could be this successful," said Mr Grant.
"It's a recognition of the hard work and the quality of the products that we make."
Grant Engineering commenced trading in Birr, Co Offaly, in 1980 and manufactures a range of oil-fired condensing central heating boilers, all designed by Stephen Grant and the company's in-house research and development team.
The company is now one of the largest manufacturers and suppliers of domestic oil-fired boilers in Ireland and leads the way in oil-fired condensing boiler technology.
Mr Grant was accompanied to the awards by his two children, Stephen jnr and Sharon.
When asked how it felt to win, he said: "It feels fantastic and it's one of the best things to ever happen to me, after the birth of my children."
In 1996, Grant Engineering (UK) Limited was formed to market all of their products there.
Because of their high efficiency levels, Grant products currently fitted save more than 350,000 tons of CO2 emissions annually.
Mr Grant said Grant Engineering was performing well through the economic downturn.
"We are very busy, business is good," he said. "In tough times like this, people are taking out old and inefficient appliances and replacing them with our highly efficient product."
Mr Grant (63) also said he had no intentions of retiring. "No not at all - I love what I do."
The company employs 270 people and turnover has increased significantly each year, from €48 million in 2005 to €75 million in the last financial year.
