WASHINGTON (Reuters) – The United States will struggle to meet President Joe Biden’s climate goal to decarbonize the power grid by 2035 as technology and policy take time to develop, natural resources consultancy Wood Mackenzie said on Thursday.

Biden took office January 1st and has since reversed many policies of Donald Trump in energy. He also joined the Paris climate agreement, setting a goal to make the U.S. grid 100% renewable energy by 2035.

Wood Mackenzie reported that 66% will be coming from non-emissions sources such as solar, wind, green hydrogen, and nuclear energy by the end of 2035. However, technologies taking time to develop mean the U.S. power grid won’t get all its energy until then.

David Brown, Wood Mackenzie Americas’ head of markets, transitions, stated that Biden’s goal still has the potential to spur efforts towards combating climate change.

Brown explained that “Even achieving this target is a positive” and would push markets and businesses to an area that will result in a net reduction of carbon emissions. This will also help to accelerate the energy transition.

Some technologies that may take some time are making hydrogen using power from wind and solar farms to be used in synthetic fuels or for industrial boilers. Other technologies will require patience include capturing carbon dioxide from fossil fuel plant before it reaches the atmosphere. The report stated that there will be a shortage of transmission lines for electricity generated from renewable energy, which must also be addressed.

An official from the Biden Administration spoke out on Wednesday to praise Biden’s achievements so far.

According to the official, “We can achieve both our climate goals as well as ensuring that the energy transition takes account of the needs and interests the middle class. They experience very direct changes in energy prices. This will help us meet the world’s energy demands once the economy has recovered from the pandemic.”