Renewable Energy

Abstract

Renewable energy encompasses the fundamental means of producing clean energy for the new clean energy economy. The goal of using these forms of energy is to work towards electrification of our activities in life and work and to stop burning natural resources to produce that electricity. This means non-emitting renewable energy for generation of electricity. From early and non-cost-effective beginnings 50 years ago, renewable energy systems have become cost-competitive, or nearly so, and have as a sector produced nearly three quarters of a million new jobs in the past few years. Renewable energy sources, mainly wind, solar PV, and hydropower (which has been cost-effective for centuries), now comprise just over 15% of domestic electrical generation. A unique aspect of renewable energy sources is that many can be scaled to home or business use, to city scale, and even to regional grid scale applications. In fact a half dozen US cities are already utilizing renewable energy for 100% of their electricity needs, and a dozen more are on schedule to achieve this in the short term. Hydropower continues to be an important component of renewable resources, especially in regions of high rainfall and already existing dams and reservoirs. Reservoirs can be utilized as a pump-storage mechanism for meeting peak energy needs to bolster other energy storage systems, such as batteries for wind and solar. The use of biomass to generate ethanol for transportation represents a midterm bridging solution to fossil fuels and perhaps a long-term resource for liquid fuel needs in select sectors. Scaling up such renewables as solar PV to supply electricity to entire communities is being accomplished in the southwest, where nearly a million homes are supplied their electricity through six large solar farms in California and Arizona. There are also significant moves to integrate renewables, in particular rooftop solar PVs, with microgrid arrays in large cities. Renewable energy resources are a key part of a comprehensive sustainable energy policy for the United States.