California Computer Efficiency Standard Nears Finish Line

Mon, 10/10/2016 - 14:20 -- MrGreen

Is California ready to approve the nation’s first mandatory efficiency standard for computers, monitors and signage displays?

It appears so. Earlier this year, I wrote about the California Energy Commission’s (CEC) initial proposed requirements (California Continues Drive for Computer and Display Efficiency). After a good deal of discussion with industry stakeholders, resulting in some specification and timing modifications, the CEC has now published their Efficiency Rulemaking Express Terms, which they hope will to be the final regulatory language approved by year end. The Commission believes that consumers and businesses will save over $370 million in energy costs from these standards.

Computers

Covered in this computer regulation are desktops, notebooks (including mobile gaming systems), thin-clients, small-scale servers, and workstations. Excluded are tablets, smartphones, game consoles, handheld gaming devices, servers other than small-scale units, and industrial computers. The CEC believes that the core opportunity for computer energy savings is in limiting the unit's energy consumption during non-productive idle, standby, and off modes.

The proposed regulation harmonizes with the ENERGY STAR Program Requirements for Computers version 6.1, adopting a Total Energy Consumption (TEC) approach. A computer's TEC is calculated using the following formula:

ETEC = (8760 ÷ 1000) × (POFF × TOFF + PSLEEP × TSLEEP + PLONG_IDLE × TLONG_IDLE + PSHORT_IDLE × TSHORT_IDLE)

Where: POFF = measured power consumption in off mode (W), PSLEEP = measured power consumption in sleep mode (W), PLONG_IDLE = measured power consumption in long idle mode (W), PSHORT_IDLE = measured power consumption in short idle mode (W), and TOFF, TSLEEP, TLONG_IDLE, and TSHORT_IDLE are mode weightings as specified in ENERGY STAR Program Requirements for Computers version 6.1, Table 3.

A computer’s maximum allowable annual energy consumption (per table 2) is determined partly by its expandability score (ES). ES is used to correlate the power supply sizing necessary for a computer to provide the required power to the core system plus any potential expansions through internal or external ports. ES is calculated by summing the products of each port score (per table 1) multiplied by the number of offered ports in the system (when sold) and then adding 100 to the resulting score.

Table 1. Proposed computer energy consumption standards

Port TypePort Score
USB 2.0 or less5
USB 3.010
USB C15
USB-PD100
PCI slot other than PCIe x1625
PCIe x16 or higher75
Thunderbolt 2.0 or less20
Thunderbolt 3.0 or greater100
M.210
IDE, SATA15

Table 2. Proposed computer energy consumption standards

Computer typeAnnual Energy Consumption (Max) (eff. 1/1/2019)Annual Energy Consumption (Max) (eff. 7/1/2021)
Desktops, mobile gaming systems, and thin clients
With ES ≤ 25050 kWh/yr + applicable adders 50 kWh/yr + applicable adders
With 250 < ES ≤ 425 80 kWh/yr + applicable adders60 kWh/yr + applicable adders
With 425 < ES ≤ 690 100 kWh/yr + applicable adders75 kWh/yr + applicable adders
With ES > 690None, must meet workstation requirementsNone, must meet workstation requirements
Notebook and portable all-in-ones
All30 kWh/yr + applicable adders30 kWh/yr + applicable adders
Power supply minimum Power Factor (measured at full load)
(Excludes EPSs)0.9 PF0.9 PF

A partial listing of the applicable energy adders are shown in table 3.

Table 3. Partial listing of proposed computer applicable adders

FunctionDesktop, Thin-Client, Mobile Gaming System Adder (kWh/yr)Notebook Adder (kWh/yr)
System Memory4 + 0.15 × C (C = capacity in GB)4 + 0.15 × C (C = capacity in GB)
Energy Efficient Ethernet0.90.9
Storage3.5 inch Drive: 26
2.5 inch Drive: 4.5
Solid State Memory: 0.5
Solid-State Hybrid Drive (SSHD):1.0
All Other: 26 per storage dev.
2.6 per storage device
Integrated Display
Where: d = diagonal measurement of the display (in), r = display’s megapixel resolution, A = viewable screen area (in2), EP=0 for displays that are not enhanced performance displays; Refer to Table V-8 in the CEC Express Terms for more info.
For d ≤20: (8.76×0.35×(1+EP) ×
[(4.2×r)+5.7]) ×0.8;

For 20<d<23: (8.76×0.35× (1+EP) ×
[(4.2×r)+(0.02×A)+2.2]) ×0.8

For 23≤d<25: (8.76×0.35×(1+EP) ×
[(4.2×r)+(0.04×A)-2.4]) ×0.8

For 25≤d: (8.76×0.35× (1+EP) ×
[(4.2×r)+(0.07×A)-10.2]) ×0.8

Resolutions greater than 6
megapixels shall use 6 for r.
8.76×0.3× (1+EP) ×
[(0.43×r) +(0.0263×A)]

Resolutions greater than 6
megapixels shall use 6 for r.

Additionally, the computers must:

  • Transition into sleep or off mode ≤ 30 minutes of user inactivity. Sleep mode power limits are described in greater detail in the Express Terms.
  • Transition connected displays into sleep mode within 15 minutes of user inactivity

Workstations

Workstations, including small scale servers and high expandability computers, must meet the following efficiency requirements, starting January 1, 2018:

  • Be powered by an internal power supply meeting 80+ Gold efficiency as shown in table 4 below or an EPS meeting DOE Level VI efficiency
  • Incorporate Energy-Efficient Ethernet functionality
  • Transition into sleep or off mode ≤ 30 minutes of user inactivity
  • Transition connected displays into sleep mode within 15 minutes of user inactivity

Table 4. Power supply requirements for small-scale servers, high expandability computers, mobile workstations, and workstations

115V power supplies
10% load Eff.20% load Eff.50% load Eff.100% load Eff.Power Factor Correction
-87%90%87%0.9 at 50% load
230V power supplies
10% load Eff.20% load Eff.50% load Eff.100% load Eff.Power Factor Correction
-88%92%88%0.9 at 50% load

Computer Monitors

Computer monitors with a diagonal screen size between 17" and 61" are regulated using modal metrics, limiting power consumption in on-mode, sleep-mode, and off-mode. Allowable on-mode power is calculated based on monitor resolution, diagonal screen size and viewable screen area. The proposed limits for products manufactured after January 1, 2019 are shown in the table 5. Monitors with touch screen capability are allowed an additional one watt in on-mode power. Monitors must consume less than or equal to 0.7 W and 0.5 W in sleep-mode and off-mode, respectively, or less than or equal to 1.2 W sleep- and off-mode combined.

Table 5. Power Consumption Standards for Computer Monitors

ResolutionDiagonal Screen Size (in)Monitor On-Mode Power Consumption (W)
≤ 5 MP17" ≤ d ≤20[(6.0×r) + (0.025×A) + 3.7] ×applicable adder
20" < d <23"[(4.2×r) + (0.02×A) + 2.2] × applicable adder
23" ≤ d <25"[(4.2×r) + (0.04×A) – 2.4] × applicable adder
25" ≤ d <30" [(4.2×r) + (0.07×A) – 10.2] × applicable adder
30" ≤ d ≤61"[(6.0×r) + (0.1×A) – 14.5] × applicable adder
> 5.0 MP17" ≤ d ≤20"[25 + (0.025×A) +3.7] × applicable adder
20" < d <23"[25 + (0.02×A) +2.2] × applicable adder
23" ≤ d <25" [25 + (0.04×A) – 2.4] × applicable adder
25" ≤ d <30" [25 + (0.07×A) – 10.2] × applicable adder
30" ≤ d ≤61"[25 + (0.1×A) – 14.5] × applicable adder

Notes: A = viewable screen area (in2), d = diagonal measurement of the display (in), r = megapixel resolution. Applicable adders can be found in Table V-5 in the Express Terms.

Commercial Signage

Commercial signage displays (excluding electronic billboards and digital picture frames) will follow the state’s current efficiency standard for televisions. The requirements are shown in table 6 below. The display must also automatically enter standby-passive or standby-active mode after no more than 15 minutes without video or audio input to the display.

Table 6. Power Consumption Standards for Signage Displays

Screen Size Area (in2)On-mode Power (PON_MAX) (W)Standby-passive Mode Power (W)Minimum Power Factor (for P ≥ 100 W)
A < 1400(0.12×A) +2510.9

The CEC plans to hold a Lead Commissioner Meeting on October 10th at the Commission headquarters (1516 Ninth Street, Sacramento, CA) to receive oral comments on the rulemaking. A vote to adopt the standards is planned at a public meeting on November 9th at 10 AM at the same location. For the complete proposed requirements, download a copy of the 2016 Appliance Efficiency Rulemaking, Express Terms for Computers, Computer Monitors, and Signage Displays here. For a copy of the 2016 Appliance Efficiency Rulemaking, Staff Report: Final Analysis, click here.