Summary
Massive in size and impact, today’s electrical power system propelled the United States through the Industrial Revolution toward prosperity, making electricity accessible to Americans across the country on rural farmsteads and city streets.
What started in Wisconsin in 1882 with the nation’s first commercially operated power plant expanded along with our appetite for energy. Today, a spider- web network of transmission lines connects generation sites tucked away in rural countrysides to distribution areas hundreds or thousands of miles away.
Once an innovation, this aging infrastructure requires new capabilities to integrate emerging and renewable energy sources more effectively.
The Challenge
Inefficiency
Fossil fuel sources like coal, natural gas and petroleum generate nearly 68 percent of electricity in the U.S. (EIA, 2013). When a conventional power plant converts carbon- based fuel into electricity, two-thirds of the energy escapes through heat loss.
Positioning generation closer to where energy is consumed would allow the waste heat to be captured, recycled and turned into useful heat with combined heat and power generating systems (CHP). These systems are already being used in the U.S. and extensively in some European countries. The University of Wisconsin–Madison’s west campus CHP system achieves 70 percent efficiency when running in co-generation mode.
Renewable energy and grid expansion
Renewable energy capacity is growing worldwide. However, these resources are not distributed evenly. In the U.S., solar is easier to capture in Arizona or New Mexico than in Wisconsin or Minnesota; the best wind resources are located on the east and west coasts. Regardless of what source is used to create electricity, global energy demands continue to increase. As we use more electricity, we will need to generate, transmit and distribute more power. This presents challenges, both in terms of economics and public acceptance.
In developing countries where renewable energy is available, but widespread infrastructure doesn’t exist, the creation of a microgrid could give communities an opportunity to use renewable energy resources locally.
What can we do?
Building stronger, more efficient energy systems can help us make the most of our natural resources, keep up with rising demand and increase accessibility to electricity in parts of the world where utility-scale systems are unrealistic.
We are learning how to develop energy systems that improve efficiency by moving generation closer to the consumer and create opportunities to utilize waste heat. We are designing systems that have flexibility for clean energy sources and boost reliability with smaller networks that can operate independently or with the traditional grid.
Addressing the Challenge: Microgrids
A microgrid is a small, self-contained electric-power grid with the capability to connect and disconnect seamlessly from the traditional grid. They include all the components of the traditional energy infrastructure (generation, distribution, consumption) shrunk to accommodate a smaller consumer base like individual buildings, hospitals, military bases, neighborhoods or universities.
Increasing efficiency with community solutions
Because it can connect and disconnect from the traditional grid, a microgrid can reduce demand for electricity from generation sites that are far away in favor of more localized energy generation. A closer generation site provides opportunities to utilize waste heat, and eliminates some of the losses from long-distance transmission and distribution. This gives communities flexibility in design and use of energy sources, and can significantly improve the overall efficiency of electricity generation.
Cleaner energy resources
The wind isn’t always blowing and the sun isn’t always shining. Microgrids reduce carbon emissions by incorporating electricity generated from intermittent renewable sources. To maintain reliability for consumers, microgrids can connect to the traditional grid when these sources are not generating power. When producing in excess, the energy can contribute to the grid supply and reduce demand for electricity from centralized power plants.
Reliability and stability
The U.S. Department of Energy estimates that power outages and grid failures cost American businesses $100 billion annually. But, when interruptions occur to grid supply, microgrid consumers could switch to electricity generated locally by distributed energy sources. This creates a more reliable energy supply and is beneficial during natural disasters. For utilities, microgrids that are producing excess power can contribute to the grid and help meet peak demands.
More to explore
If you're interested in learning more about microgrids, check out the stories, educational materials, events, and resources below.
Renewable Energy Access and Grid Resilience
September 29, 4:30pm
Microgrids and other technologies may offer powerful ways to enable energy access, increased grid resiliency, and higher percentages of renewable energy generation. Join us to learn more about how we can address these opportunities and challenges and aid the transition toward 100% renewable electricity.
Learn more and register for the event
Bigger electricity menu means smaller grids
When Hurricane Sandy caused the power to go out in parts of New York City in 2012, the lights stayed on in one building on lower Fifth Avenue. The building—The Brevoort—was able to provide electricity, heat, and water to 1,500 people during the emergency thanks to microgrid technology developed in part at the University of Wisconsin–Madison.
Read the full story
Microgrid Sustainable Energy Exploration Station
This Exploration Station is designed to introduce learners to the basics of microgrids and new approaches to generating and distributing electrical power in communities.
Check out our microgrid exploration station