Can an entire city switch to LED lights?

Over the past few years, LEDs have become increasingly common, as they provide long-lasting performance for a fraction of the energy used by traditional lights. Think of the latest generation of LED TVs, modern car lights or even household light bulbs. Many LEDs today have an expected lifespan of over 20 years while using 80% less energy to produce the same amount of light. With savings like this, imagine switching over an entire city to LED lighting.