The purpose of measurement and verification (M&V) is to establish the potential of a project's measures to save demand and energy and to determine the actual savings produced by those measures.
In the C&I Standard Offer Program, Project Sponsors are responsible for planning and conducting all the M&V activities associated with their projects. They are required to submit, as part of the Final Application, an M&V plan that describes the specific activities, tools, and calculations the Sponsor intends to use to determine the projects' actual savings.
This section of the site provides guidelines and instructions to help Project Sponsors develop their M&V plans. Also discussed are the site inspections that CenterPoint Energy conducts during the program process to verify project site conditions.
Measure-specific M&V approaches
M&V procedures will vary in detail and rigor depending on the measures installed. For each installed measure, the chosen procedures will depend upon the predictability of equipment operation, the availability of evaluation data from previous programs, and the benefits of the chosen M&V approach relative to its cost.
Project specific M&V procedures may be classified according to three distinct approaches that represent increasing levels of detail and rigor:
- Deemed savings: Savings values are stipulated based on engineering calculations using typical equipment characteristics and operating schedules developed for particular applications, without on-site testing or metering. This approach is designed for use with some lighting efficiency and controls projects, some cooling equipment projects, and window film applications.
- Simple M&V: Savings values are based on engineering calculations using typical equipment characteristic and operating schedules developed for particular applications, with some short-term testing or simple long-term metering. For example, chiller energy and demand savings can be determined using the simple approach by comparing rated efficiencies of high-efficiency equipment to standard equipment, and using kW spot-metering and simple long-term kWh metering.
- Full M&V: Savings are estimated using a more detailed method than in the deemed savings or simple M&V approaches through the application of metering, billing analysis, or computer simulation. These methods will need to be developed in accordance with the 1997 International Performance Measurement and Verification Protocol (IPMVP), which represents the starting point for industry practice. Portions of the IPMVP have been adapted for use with this program (see below).
M&V guidelines have been developed for use in this program. To download a guideline, simply click on a filename in the following table. Note that these files are in PDF format, available for viewing and printing only with Adobe Acrobat Reader®.
| Measure/approach type | M&V guideline (click to download) |
| Retrofit lighting | Retrofit lighting.pdf (518K) |
| Retrofit lighting efficiency and controls | Retrofit lighting with controls.pdf (635K) |
| New construction lighting efficiency | NC lighting.pdf (490K) |
| Cooling equipment retrofits | |
| New construction cooling equipment installation | NC cooling.pdf (401K) |
| Motor retrofits | Retrofit motors.pdf (329K) |
| High efficiency motor installation in new construction | NC motors.pdf (207K) |
| Window film installation in existing buildings | Retrofit windows.pdf (318K) |
| Stipulated savings factors for retrofit projects | Retrofit stipulated factors.pdf (239K) |
| Stipulated savings factors for new construction projects | NC stipulated factors.pdf (164K) |
| Generic variable loads for retrofit projects | Retrofit variable loads.pdf (287K) |
| Generic variable loads for new construction projects | NC variable loads.pdf (254K) |
| Billing analysis and regression models for retrofit projects | Retrofit billing analysis and regressions.pdf (233K) |
| Computer modeling and analysis for retrofit projects | Retrofit simulation analysis.pdf (349KB) |
| Calibrated simulation analysis for new construction projects | NC simulation analysis.pdf (297K) |
Project Sponsors will need to adapt these guidelines to their specific projects when developing the M&V plan required for program participation. Project Sponsors may recommend an M&V approach not covered in these guidelines; however, any alternate approach must be approved by CenterPoint Energy and adhere to IPMVP standards.
The time required to complete M&V activities will range from less than one month to up to 12 months, depending on the approach chosen.
Sampling guidelines
When preparing the Final Application, a Project Sponsor is required to document each fixture or piece of equipment that is part of a project. Equipment with similar functional uses may be grouped together for M&V purposes. Once the equipment has been grouped, a sample of each grouping's equipment may be monitored and the results used to estimate the operating hours for all of the fixtures or equipment within that group. (For more information on specific equipment groupings, see the measure-specific M&V approaches for that equipment type.)
The table below shows how large the sample size must be to provide a reliable estimate for varying sizes of groups. The initial sample sizes represent 80% confidence/20% precision and have a coefficient of variation of 0.5; the suggested sample sizes have been increased by 10% to compensate for equipment failure or loss.
|
Group
population |
Initial
sample size (80/20) |
Suggested
sample size (80/20 plus 10%) |
|
4
|
3
|
4
|
|
5
|
4
|
5
|
|
12
|
6
|
7
|
|
16
|
7
|
8
|
|
20
|
7
|
8
|
|
25
|
8
|
9
|
|
30
|
8
|
9
|
|
35
|
8
|
9
|
|
40
|
9
|
10
|
|
45
|
9
|
10
|
|
60
|
9
|
10
|
|
65
|
9
|
10
|
|
70
|
9
|
10
|
|
80
|
10
|
11
|
|
90
|
10
|
11
|
|
100
|
10
|
11
|
|
125
|
10
|
11
|
|
150
|
10
|
11
|
|
175
|
10
|
11
|
|
200
|
10
|
11
|
|
300
|
10
|
11
|
|
400
|
11
|
13
|
|
500
|
11
|
13
|
The Project Sponsor may propose an alternative approach to determining sampling sizes, but it must be approved by CenterPoint Energy and be based on sound statistical principles.
M&V plan requirements
The M&V plan describes the potential for the project to achieve demand and energy savings and describes the specific activities the Project Sponsor intends to perform to determine those savings.
In general, a project-specific M&V plan should:*
- Describe the project site and the project; include information on how the project saves energy and what key variables affect the realization of savings.
- Describe the M&V approach to be used.
- Indicate who will conduct the M&V activities and prepare the M&V analyses and documentation.
- Define the details of how calculations will be made. List analysis tools, such as DOE-2 computer simulations, and/or show the equations to be used. A complete "path" should be defined indicating how collected survey and metering/monitoring data will be used to calculate savings. All equations should be shown.
- Specify what metering equipment will be used, who will provide the equipment, its accuracy and calibration procedures. Include a metering schedule describing metering duration and when it will occur, and how data from the metering will be validated and reported. Include data formats. Electronic, formatted data read directly from a meter or data logger is recommended for any short- or long-term metering.
- Define what key assumptions will be made about significant variables or unknowns. For instance: "actual weather data will be used, rather than typical-year data," or "fan power will be metered for one full year for two of the six supply air systems." Describe any stipulations that will be made and the source of data for the stipulations.
- Define how any baseline adjustments will be made.
- Describe any sampling that will be used, why it is included, sample sizes, documentation on how sample sizes were selected, and information on how random sample points will be selected.
- Indicate how quality assurance will be maintained and replication confirmed. For instance: "The data being collected will be checked every month," or "to ensure sufficient accuracy, results will be subjected to third-party review by the ABC company."
Project Sponsors should work with CenterPoint Energy to develop an M&V plan that is appropriate for their projects. To help Project Sponsors get started CenterPoint Energy has created M&V plan templates for certain projects. To download a template (a Microsoft® Word® file), click on the filename in the table below.
| Description | Click to download |
| Lighting, deemed savings | light_dmd.doc (14K) |
* This list is from the 1997 International Performance Measurement and Verification Protocol (IPMVP).
Site inspections
Over the course of a project, CenterPoint Energy conducts two site inspections. A pre-installation inspection is performed as part of the Final Application review; a post-installation inspection is performed following the Project Sponsor's submission of the Installation Report.
Pre-installation inspection
CenterPoint Energy will contact the Project Sponsor and complete the pre-inspection within 30 days of the receipt of a completeFinal Application. The purpose of this inspection is to verify the following:
- The accuracy of the equipment survey. For most measures the accuracy of the equipment quantity and nameplate information is verified. For lighting measures, the requirement for acceptance is that the installed demand of the sample must be within +/- 5 % of the total demand submitted on the survey form.
- The M&V plan is appropriate for the measure, and the necessary M&V activities are being performed.
- All existing equipment listed in the Final Application is still in place and operational.
- New equipment installation, or preparation for installation, has not begun.
Post-installation inspection
This inspection, conducted by CenterPoint Energy within 30 days of its receipt of a completeInstallation Report, verifies the following:
- The installation of the equipment specified in the approved Final Application. For most measures the accuracy of the equipment quantity and nameplate information is verified. For lighting measures, the requirement for acceptance is that the installed demand of the sample must be within +/- 5 % of the total demand submitted on the survey form.
- The M&V plan is being followed in accordance with the approved Final Application.
For both inspections, the presence of at least one representative of the Project Sponsor familiar with the project and with the facility is required. When electrical measurements are necessary, the representative is required to perform any necessary disruptions in equipment operation, the opening of any electrical connection boxes, or the connection of current and power transducers.
If an inspection cannot be completed in a timely manner because the representative is unfamiliar with the facility or project, the project will fail the inspection. A project has two chances to pass each type of inspection (pre or post); after failing two inspections, the Project Sponsor must pay the cost incurred by CenterPoint Energy for performing additional inspections of that type.
