Certification and Carbon Balancing

To obtain LEED Zero Carbon certification, a project must achieve a carbon-dioxide equivalent (CO2E) balance of zero for the past year: Carbon Balance = Total Carbon Emitted - Total Carbon Avoided Carbon Emitted is calculated from delivered energy and occupant transportation. Carbon Avoided includes on-site renewable energy generated and exported to the grid, off-site renewable energy procurement, and the purchase of carbon offsets. Renewable energy generated and used on site reduces the amount of energy delivered. Environmental benefits of all renewable energy generation or procurement must be retained by the project. An overview of the carbon balance is provided in Table 1. 

Table 1. Carbon Balance

If purchasing Energy Attribute Certificates (EACs), also known as Renewable Energy Certificates (RECs), the EACs must be Green-e Energy certified or equivalent. Carbon offsets must be Green-e Climate certified or equivalent. Projects must purchase EACs or carbon offsets annually during the three year period when the certification is valid. On-site renewable energy generation and consumption will vary based on weather and operating conditions, so year to year the required purchase will vary. For LEED Zero certification review, it is sufficient for the project owner to provide a written commitment to purchase EACs or carbon offsets, as applicable, each year during the three-year period when the certification is valid in order to maintain the net zero carbon balance.

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