The main goal of improving energy efficiency in buildings is to reduce greenhouse gas emissions caused by heating and air conditioning systems. Many existing buildings were constructed without energy-saving considerations, so now the focus is on upgrading them to be more energy-efficient. This can be done by improving building design, materials, and systems while also integrating renewable energy sources like solar and wind power. By making buildings more energy-efficient and utilizing renewable energy, we can cut down on energy waste and lessen our environmental impact. Ultimately, saving energy is the best and cleanest way to power our buildings.