Mission
Empower sustainability leaders to increase their organization’s impact on decarbonizing the grid.
About Grid Impact Score
The grid impact score is a measure of a company's energy procurement strategy's impact on adding net new clean energy to the grid.
Grid Impact Score =
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1 x (% energy from High Impact Methods) +
â…” x (% energy from Medium Impact Methods) +
â…“ x (% energy from Low Impact Methods)
​The score separates procurement methods into three groups:
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High Impact Methods directly add new clean power to the grid. These include PPAs, VPPAs, and behind-the-meter generation.
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Medium Impact Methods indirectly support adding new clean generation to the grid. These include ARECs, green tariffs, shared renewables and community choice aggregation.
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Low Impact Methods support clean energy generation but have a small impact on introducing new clean generation capacity to the grid. These include unbundled RECs, utility green power programs, and competitive green power programs.
The Grid Impact Score is not designed as a precise measurement of a company's affect on the grid mix, but as an easily digestible metric that illustrates the extent to which a company’s electricity procurement supports new clean energy generation in relation to its total electricity consumption. Scores typically range from 0 to 100, with a score of 0 representing an organization that doesn't purchase any clean electricity and a score of 100 representing an organization that sources 100% of its electricity from high impact methods.
Methodology
Grid Impact Score distinguishes between clean electricity procurement method that have a High Impact, Medium Impact, and Low Impact on decarbonizing the grid. In calculating the score, electricity procured from Low Impact methods receives a 1x weight, Medium Impact methods receive a 2x weight, and High Impact methods receive a 3x weight. The score is calculated as follows:
High Impact
Grid Impact Score considers procurement methods that directly contribute to the creation of net new clean electricity generation to be High Impact. These include Power Purchase Agreements (PPAs), Virtual Power Purchase Agreements (VPPAs), and Behind-the-Meter generation.
PPAs
A Power Purchase Agreement is a long-term contract in which a buyer commits to purchasing electricity and RECs from a specific renewable energy generator, typically spanning the first 10-20 years of the project’s commercial operation. This upfront commitment provides project developers with the revenue assurance needed to secure financing. PPAs are considered High Impact because of this crucial role in supporting the project’s financial feasibility and viability.
VPPAs
Similar to a PPA, Virtual Power Purchase Agreement is a long-term contract to purchase RECs and power from a generator for a specified timeframe at the beginning of the project's commercial operation. Unlike a traditional PPA, the energy produced is not delivered directly to the buyer; instead, it is sold into the grid at market prices. The VPPA buyer then settles the difference between the market price and a strike price specified in the contract. Like PPAs, VPPAs can be used to secure financing for renewable projects, and are also considered High Impact.
Behind-the-Meter
Behind-the-Meter (BTM) generation refers to renewable energy systems, such as solar panels or small wind turbines, that are installed at a facility to directly supply its energy needs. Electricity from BTM generation is used on-site, which directly reduces the facility's grid demand. BTM generation is considered High Impact because of this direct reduction on grid reliance.
Medium Impact
Grid Impact Score defines Medium Impact procurement methods as those which either indirectly contribute new clean generation capacity to the grid or strongly signal demand for new clean energy generation. This category includes Additionality RECs (ARECs), Community Choice Aggregation (CCA), Green Tariffs, and Shared Renewables.
ARECs
Additionality RECs (ARECs) are long-term future contracts to purchase RECs from a new generation project during its first 5 or 10 years of commercial operation. Because ARECs are a forward commitment, they can be used by developers to secure financing for a generation project. However, ARECs might only make up a small portion of the project's offtake. For this reason, they're considered Medium Impact.
Community Choice Aggregation
Community Choice Aggregation (CCA) programs allow local governments to aggregate the electricity demand of their communities and purchase renewable energy on their behalf. CCAs offer customers access to higher renewable energy content than is typically available from default utility services. While these programs signal strong demand for renewable energy and often invest in local projects, their impact on new renewable generation varies. Consequently, CCAs are considered Medium Impact, as they indirectly contribute to clean energy development and support the transition to a greener grid.
Green Tariffs
Green Tariffs are utility-offered programs that allow large customers to buy renewable energy directly from the utility or via a third-party supplier through special rate structures. Customers pay a premium or agree to a long-term contract to match their electricity usage with renewably sourced power. Although Green Tariffs can support the demand for additional renewable generation, the impact is often limited to existing renewable sources or aggregated programs. Therefore, Green Tariffs are considered Medium Impact, as they promote renewable energy adoption without necessarily driving new projects.
Shared Renewables
Shared Renewables, often referred to as community solar or wind programs, allow individuals and businesses to buy or lease a portion of a local renewable energy project and receive credit for their share of the electricity generated. These programs enable broader access to renewable energy but are typically connected to existing community projects rather than new capacity. Shared Renewables are classified as Medium Impact because they support renewable energy adoption at a community level and demonstrate demand, though they generally lack the financial leverage to create additional generation capacity.
Low Impact
Procurement methods are considered Low Impact if they support existing renewable generation projects or weakly signal demand for new clean energy generation. These methods allow the buyer to claim the environmental attributes of carbon-free electricity, but they have little affect on the grid mix.
Unbundled RECs
This category refers to unbundled RECs from an existing generator purchased in arrears on a spot market. While purchasing and retiring unbundled RECs allows organizations to make clean energy claims, this method is considered Low Impact because it supports existing generators but does little to add new clean generation capacity to the grid.
Competitive Green Power Products
Competitive Green Power Products are options offered by competitive electricity suppliers that allow consumers to choose a renewable energy product. These products often pool existing renewable sources rather than funding new generation. Customers pay a premium to match their electricity usage with RECs, providing a way to demonstrate environmental commitment. However, because these products mainly support already operational renewable projects without requiring additional generation, they are classified as Low Impact in terms of grid impact.
Utility Green Power Products
Utility Green Power Products are voluntary programs offered by utilities that allow customers to purchase renewable energy, typically by paying a premium. Utilities source this renewable energy from existing projects and match it with the customer’s electricity consumption. Like other low-impact options, these products help meet renewable energy goals but primarily support pre-existing renewable sources and have limited influence on adding new capacity, leading to a Low Impact rating in terms of grid impact.
Our Team
Dave Galinski
Product Manager
Shannon Eger
Design Lead
Bilal Nyle Zafar
Data Analyst