Speaking at CEDA's State of the Nation conference in Canberra, Ms Warlick said investment in renewable energies such as wind and solar has doubled.
"Both wind and solar now represent an increasing proportion of our electricity and energy reliance something that we want to see continuing to grow," she said.
Ms Warlick said the announcement of President Obama's climate action goals a few weeks ago is an important step for the US energy sector.
"Reducing carbon emissions in our energy sector and increasing reliance on renewable energies is going to be more and more important," she said.
Also speaking as part of the global financial update panel at CEDA's conference, ANZ Chief Economist, Warren Hogan said American foreign multinationals invest significantly in Australia.
"The dominance of foreign direct investment is out of America," he said.
Mr Hogan also said that with the shifting global environment and the rise of Asian economies opens opportunities for Australia to gain investment from countries such as China.
"The amount of foreign direct investment out of China is huge," he said.
On China, Australia China Business Council Chairman, Ian McCubbin said Chinese capital investment in Australia, especially into infrastructure has slowed.
"From a China perspective…five years ago, China was falling over itself to provide capital to Australia to support natural resources projects," he said.
"That enthusiasm from the Chinese banks…especially the China Development Bank…unfortunately a lot of that emphasis has moved within those financial institutions away from Australia…into places like Latin America."
European Union Delegation Ambassador and Head, His Excellency Sem Fabrizi also discussed infrastructure investment in Europe.
Mr Fabrizi said developing infrastructure in new EU countries has been and remains a priority for the EU.
"Promoting infrastructure has always been part of the EU policy especially towards new countries who enter the European Union," he said.
Using Spain and Poland as examples, Mr Fabrizi said key projects have been built using co-financing from other countries and to integrate new countries into the wider EU network.
"You see infrastructure, airports, big ports, railway has been built with co-financing of European money, so there's a large transfer of money to allow new countries to build infrastructure," he said.