A different kind of solution to the energy problem is for builders to reduce the amount of energy required in a building. For example, it is possible to cut electricity use noticeably just by improving natural lighting and installing low-energy lightbulbs. To reduce the amount of fuel that is needed for heating or cooling, builders can also add insulation to the walls so that the building stays warmer in winter and cooler in summer. They can also consider the position to the building to take advantage of natural heating and cooling effects of the sun, the wind , and other buildings nearby. Furthermore, builders can plant trees that reduce energy use by providing shade in sunny weather and protection from cold wind.