How Cities are getting to 100% Renewable Electricity

Map of cities going 100%

There are a lot of cities making commitments and promises to go 100% Renewable Energy. Each has a different plan, timeline, and way of doing it. A map of these cities is at the 100% Renewable Site. These include such cities as San Diego, Madison, as well as Chicago announcing to power city buildings with green energy. This is very great to hear because local initiiatives can make a big impact. But, how do they do this? How does a city ensure 100% of the electricity they consume is from clean power sources? Cities are not in the business of providing electricity, and they buy electricity directly only for their buildings.

I’ll look at several case examples of how cities are getting to 100% renewable energy. There are different ways city governments can exert their influence to control where their electricity comes from. In all the examples, they must work with a conglamoration of players to get it. This includes utilities, non-profits, govenrment agencies, and corporations. They also need buy-in and a willingness from the citizens to make it happen. Many of the best examples are profiled by the Sierra Club in their Cities are Ready for 100% Clean Energy 10 Case Studies Report. Here are several case examples of actions being taken to get it done.

  1. Enact policies

One of the most direct ways cities governments are controlling the electricity use in their jurisdictions is through legislative action. This can be laws on a wide variety of issues. One of the most common is controlling demand through energy efficiency mandates. Greensburg, KS is a city that was destroyed by a tornado in 2007 and rebuilt their eletric grid with a focus on clean energy. One of the first actions they took was to require all buildings over 4,000 square feet to be LEED Platinum certified. Energy efficiency measures are a low-hanging fruit way for communities to control their electricity use.

Other policies help to promote clean energy uptake by its residents. Another action Greensburg took was to enact a Net Energy Metering (NEM) ordinance for its residents. Allowing rooftop solar to sell excess electricity back to the grid makes solar an economically more attractive option. While NEM is a very contentious issue, Greensburg made a decision to require it. In doing so, it put a priority on solar adoption. These are only two examples of policies being put into place to promote residents to make green decisions.

  1. Renewable Portfolio Standards

Renewable Portfolio Standards (RPS) are a mandate for a certain percentage of the mix of electricity to come from renewable sources. It must be followed by the utility or energy provider in the jurisdiction. It is a direct way of municipalities to dictate what the energy mix of their area looks like. It is most often done at the state level, but can also be enacted by cities. This option is being explored in Rochester, MN. The cities goal is to be 100% renewable by 2030. Part of this plan is to have a 25% RPS by 2025. 68% of its residents support requiring energy to be sourced by renewables. The cost for these resources is then incorporated into the rates.

  1. Power Purchase Agreements (PPAs)

Power Purchase Agreements are long-term contracts to buy electricity for a fixed price and amount. The benefit is that they take the risk out for both the buyer and seller. The downside is that market prices can greatly fluctuate from the original contract; although, contracts can be set-up differently to conteract this. PPAs are often needed to ensure financing gets raised for renewable energy projects. By contracting PPA, cities can gaurantee where their electricity is coming from.

Georgetown, TX secured long-term low electricity prices when it signed a 25 year deal. It was done because it was both a low-cost and reduced risk option making it very attractive to the city. PPAs are best suited for places where renewable electricity is readily accesible and the areas utility set-up is conducive to it. The unique set-up of this city owning the utility allowed it to control where the utility gets its electricity.  It could also be done by larger scale individual operations such as city buildings. It would be a good option for the city of Chicago in supplying electricity for their buildings. PPAs are a great way to control where electricity is sourced from.

  1. Buy a dam

When a city has a municipally-owned utility they are given more control over the utility. The utility is still controlled through a utility commision. One example of the control government can have over a municipally-owned utility is with the city of Burlington, VT buying a 7.4 MW hydroelectric plant on the Winooski River. This is able to provide 25% of its electricity needs. It is complemented by other souces, but it is one example of a city taking a more direct jump into how it sources its electricity. Municipally-owned utilities allow cities greater control over generation purchases.

  1. Community Choice Aggregation

Community Choice Aggregation is a very innovative way for the people of the city to come together to source their electricity. The city organizes to buy power in bulk wholesale from producers. This allows them negotiating power to dictate terms of the deal. This was done by San Jose where the city hired a private partner to develop, finance, and operate the program. It is very similar to community solar projects where communities come together to make a deal for solar power projects. Community Choice Aggregtion puts cities deeper into the details of sourcing their electricity, but also allows them greater control.

  1. Renewable Energy Credits

One relatively easy way that cities can claim 100% renewable energy is with Renewable Energy Credits (RECs). RECs are claims on renewable generation created when a source generates clean energy. They are essntially an accounting method of tracking renewable energy generation. One example of a city doing this is Grand Rapids, MI. Although, they get some kickback because the buyer can still be physically getting their electricity from any source. One of the issues brought up with RECs is that a buyer can buy RECs for 24 hours worth of their demand when a clean source would never be able to provide electricity for all of those hours. One answer to this dilemna is that there are different levels of RECs with different specifications. The important thing is that RECs support renewable energy by providing an additional revenue source and making them more economically viable. RECs allow cities to claim their electricity is sourced from renewable generation.


All of these ways of accomplishing 100% renewable energy require cities to understand their unique situation and exert their influence within these constrains. Each uses a combination of these tools to better control from where their electricity is generated. It isimportant that they work with other stakeholders including utilities, residents, developers, and other agencies. All of these cities in Ready for 100% Clean Energy 10 Case Studies Report also have a clear plan and an office in charge of the plan. It usually includes a current state with baseline emissions data, and action steps for getting to the future state.In the end, this long journey starts with the starting step of deciding to go 100% Renewable.


Other Sources:

Repowering Port Augusta –

Presents options calculating capacity and financing. IRENA –

Energy Roadmaps –