The demand charge has been in place with Benton PUD’s commercial, industrial, and large irrigation customers for most of our 77-year history, so it is not a new concept. While some costs of regional power grid generation and transmission have been included in longstanding demand charges, historically the biggest cost drivers were utility investments in equipment and wires required to avoid overloading local community electric delivery systems during high customer usage periods. Now aggressive clean energy laws are beginning to put a premium on the cost of supplying electricity during the hours of the day when customer demand is highest.
Benton PUD performs a Cost-of-Service Analysis study (COSA) annually that provides what level each rate component should be set at. A COSA is a standard tool that employs industry accepted methodologies to ensure fair allocation of costs and provides a basis for rate design. The COSA calculates what the daily system charge, demand charge, and energy rate for all rate classes should be, including residential. Historically, residential meters did not measure a demand read. As a result, the demand charge has been embedded in the energy charge, which is common in the utility industry. Through the installation of Advanced Metering Infrastructure (AMI), all meters now provide a demand reading which makes a demand charge for all metered services possible.
The results of the COSA study show 61% of the costs to serve residential customers are fixed for Benton PUD, and 39% are variable. However, historical residential rate design has 17% of revenue collected through a fixed charge (daily system charge) and 83% collected through a variable charge (energy rate). The graph below illustrates COSA results, the current rate design, historical rate design, as well as what comprises variable and fixed costs.
The COSA calculates what the rates should be to align how customers are billed with the nature of costs for the utility. For example, the energy rate should align with the cost of electricity received from BPA that is generated largely with hydro power as well as nuclear power. The daily system charge and demand charge are rates that align more closely with utility fixed costs such as peak capacity backup capabilities, transmission lines, substations, distribution lines and transformers, and customer support services. For residential customers, the COSA study shows the energy rate should be decreased, while a demand charge should be added, and the daily system charge (base charge) should be increased. A breakdown of the average monthly bill of $115 using COSA rates are as follows: variable costs 39% or about $45 (energy) and fixed costs 61% or about $70 (daily system charge $34 and demand charge $36) per month. For comparison purposes, the breakdown of the monthly average bill using current rates is as follows: variable costs 77% or about $89 (energy) and fixed costs 23% or about $26 (daily system charge $19 and demand charge $7) per month. Benton PUD is not proposing to change rates to be in full alignment with the COSA study.
Most utilities have similar results with COSA studies, and many have opted to raise the base charge to a level of $30-$40 per month, which means every customer pays a higher monthly fixed charge regardless of how they use electricity. Instead of raising the base charge to the full COSA amount of $34, the implementation of $1 per KW demand charge begins to provide for the recovery of fixed costs, but in a manner that is proportional to a customer’s highest usage during peak hours. The initial demand rate will be set at $1.00/kW with a corresponding reduction to the energy rate and may be gradually further unbundled in future years.
We are implementing a change to our residential rate design to send a small price signal incentivizing customers to consider shifting some of their electricity use to hours other than those corresponding to periods of maximum power grid demand. In addition to ‘keeping the lights on,’ it is our job to be forward-thinking and to anticipate and plan for increases to our costs, which are your costs. With some of the most aggressive clean energy laws and regulations in the nation, including the Clean Energy Transformation Act (CETA) and Climate Commitment Act (CCA), Washington state’s unprecedented regulation of electric utilities is beginning to put a premium on the cost of supplying electricity during the hours of the day when customer demand is the highest. Think early morning and late evening during winter cold and early evening during summer heat.
We know energy policies can be confusing and politically polarizing, but the simple matter is that electricity is a just-in-time service where the unforgiving laws of power grid physics requires supply of electricity to precisely match demand on a minute-by-minute basis. While we are just beginning to experience increasing cost pressure during high customer demand periods, we anticipate this pressure will grow over time as utilities are forced to rapidly replace controllable, dependable, and affordable technologies with intermittent and variable wind and solar to satisfy CETA’s 100% non-greenhouse-gas emitting electricity requirements.