Energy Literacy
For those of you who want to learn more about Boulder’s energy grid, what “the grid” is, and more about energy, here is a helpful list of information:
- Xcel Energy is one of many shareholders owned electrical utility companies. Alternatives to the standard shareholder option include cooperatives and municipalities.
- “The grid” is made up of energy production facilities (coal burning plants, wind turbines, etc.), substations which provide regulation, and transmission lines that distribute power. In July, 2025, the U.S. set a new record, with the lower 48 states setting a peak demand of 759,180 megawatts.
- Energy is measured in Watts. Watts can be thought of as energy over time. 1000 Watts per hour is known as a kilowatt-hour (kWh). 1 kWh is roughly equal to the amount of energy required to run an oven for 1 hour. In 2022, the average annual electricity consumption for a U.S. residential utility customer was 10,791 kWh.
- The amount of energy that one solar panel can produce in a year is dependent on many variables. Local Boulder solar gardens get about 750 kWh a year per panel.
- Fossil fuels are energy sources. They are nonrenewable on relevant time scales and emit greenhouse gasses. Coal is the dirtiest energy source and natural gas is the “cleanest”.
- Renewable clean energy sources are renewable in production and do not emit greenhouse gasses. In 2024, renewable energy sources provided ~23% of utility scale U.S. electricity generation.
- Problems with 100% renewable grids are managing demand and maintaining profitability include:
- Ramp Problem. Renewable energy is an intermittent power source, meaning that its power production is not always constant. This can lead to huge surges and reductions of power production during certain times of the day. Without the proper infrastructure supporting renewable energy like energy storage installations, the possibility of blackouts increases without a traditional baseline or peaking power sources like thermal or nuclear plants.
- Duck Curve problem. This issue is mainly focused on solar. Solar power production peaks in the day, but peak electricity demand occurs in the evening. This mismatch threatens the stability of a renewable grid and could require a backup power source to supplement demand.
- Marginal producer problem. Currently power providers receive money from selling electricity which is sold at the marginal cost of production. The marginal cost of production is dictated by the power source that is the marginal producer, the provider whose electricity production is necessary in meeting power demand. Currently, the marginal producer is generally natural gas or thermal plants that have relatively high marginal costs, which mean a higher cost of electricity.
- An identified problem with renewable energy is that it has a near zero marginal cost as the power sources require no purchased fuel to run. In cases where renewables become the marginal provider, electricity costs plummet to near zero, and sometimes in the negatives. While this seems like a positive thing, the companies that provide us energy require profit to stay in operation. Drastic changes will need to be made in order for a fully renewable grid to feasibly be implemented and be profitable to those who run it.
Solutions and financial advantages of renewable energy:
- In a clean grid, demand can be managed through better storage and better-connected grids.
- If you put solar panels on your house, you might have the ability to send excess electricity produced by your panels back to the grid in exchange for credits that can offset the cost of energy you need at night. This is called net metering, and different states and electricity companies have varying policies that dictate how much electricity can be allowed back into the grid and how much one can be credited for it. On average, 20-40% of the average solar energy system’s output is sent back to the grid.
- If you cannot purchase solar for your home, you can buy Renewable Energy Certificates (RECs). Buying into these programs will mean your energy is coming from a renewable production site instead of a non-renewable production site.
- When you buy a REC, you will receive a bill credit on your energy bill. A bill credit is dollar savings that correspond to the amount of energy your REC produces.
Boulder’s Energy Goals
Boulder has some very aggressive energy and climate targets which makes our ZEN team glad to have our headquarters here. To read more about it from the source please visit Boulder’s Climate Action Plan page. The graphics below show some of the areas of focus: where we are, where we want to be, and by when:
This graphic defines Boulder’s goals and targets.
This graphic shows Boulder’s emissions reduction progress.
This graphic shows Colorado’s goals for emissions reduction and renewable energy use.
This graphic shows Colorado’s energy profile.
This graphic shows the sources of greenhouse gas emissions in Boulder by type.
To compare Boulder to the country at large, here are some general electricity usage and generation stats for the US:
This graphic shows the make up of the U.S.’s electricity generation sources.
