Questions and answers about the Zero Net Carbon Model
- Determine the least-cost portfolio of generation resources that can achieve carbon-neutrality by 2030
- Assess at a high level, the risks and risk mitigation measures associated with achieving or exceeding carbon neutrality.
- Define the average carbon emission rate of the existing regional power "market" - 1,803 lb/MWh was used as the average carbon emission rate for the regional power market based on the published eGrid Rockies data for non-baseload generation. Pace Global assumed that any purchases or sales by Platte River would not be large enough to impact baseload generation units, but rather would impact the output and resulting emission of intermediate or peaking generation units in the region. Under this approach, each non-carbon MWh that Platte River sells into the market serves to "offset" the generation of an existing fossil fueled generation unit in the broader regional market, and results in a reduction of 1,803 lb/MWh to the overall market emissions.1
- Construct a carbon accounting method to track the annual carbon emissions, carbon offsets, and achievement of carbon-neutrality.
- Establish a starting level of non-carbon energy requirements as a percentage of Platte River’s load. This is done because the model cannot simultaneously solve for both the emission reductions required to hit net zero carbon emissions and the least-cost portfolio, so model iteration is required. First, we pick a starting minimum non-carbon level (approximately 90%), solve for the least-cost portfolio, check to see if carbon-neutrality is met, and then adjust the non-carbon percentage to ensure carbon-neutrality is met in each year from 2030 and beyond.
- Solve for the least-cost mix of generation technologies based on capital costs, fixed and variable operations and maintenance costs using hourly production modeling over the forecast horizon.
- Assess the results to determine if carbon-neutrality is achieved each year beginning in 2030.
- Modify the generation capacity available from the non-carbon sources until carbon-neutrality is achieved in 2030 and then maintained beyond 2030.2
2 Increments of 3% were used to adjust for carbon neutrality – the iteration process was stopped when carbon neutrality was achieved. Using smaller increments would have allowed us to meet the standard without over-achieving in each year but we do not expect a material change in buildout and associated costs.
Our focus for this modeling effort is to find the least-cost method of achieving a non-carbon resource mix using current resource cost estimates.
You are involved in the process. Our Board of Directors listened to the requests of stakeholder groups and citizens, and agreed to model a 100 percent net non-carbon resource scenario for all four communities. Once the modeling is complete and our board is briefed, we plan to conduct meetings with stakeholders and interested parties. During these meetings, we will discuss in greater detail the elements of the modeling and take input concerning the data within it. We will use this feedback to fully inform our leaders so they may make better decisions concerning our energy future.
Platte River contracted with Pace Global because it is a highly respected utility industry leader in strategic business consulting, with significant experience and expertise in strategic energy resource planning. A division of Siemens Business, Pace Global has provided innovative services to support the execution of business strategies, complex energy transactions, asset development, and operations focusing on select markets in the Americas.
Platte River currently delivers wholesale energy at the lowest rate in Colorado and does evaluate rate impact as part of its decision-making process. While the model prepared by Pace Global explains the impact to production costs from a ZNC model, overall costs are unknown. Further refinements would be needed to determine the complete impact to rates.