A
new report from the Natural Resources Defense Council put the PS4 and
Xbox One under the power efficiency microscope and came back with less
than glowing things to say about the new devices. According to the
organization, both consoles draw more power than they should despite
heavy investment in power-saving technologies.
The
long-term impact? ”Over five years, the Xbox One’s 250 kilowatt hours
per year usage represents roughly $150 in electricity costs, enough to
buy two or three new games!”
True. But the tone of the original
blog piece is a bit overdramatic — particularly given that these are
figures we could generate for virtually any non-critical appliance that
runs on a daily basis.
First, the NRDC does have a point: The Xbox One and PS4 use significantly more powerthan
their predecessors. Data from various sources, including NRDC, suggests
that power consumption is far higher than it ought to be, at 80W for
Blu-ray playback for the Xbox One and 90W for the PS4. Blu-ray players
from 2009 (Samsung’s BD-P3600) was
tested by CNET and found to consume 22W against the PS3 Slim’s 81W. Not much improvement there.
The PS4 consumes more power than the Xbox One in every mode
except Connected
Standby, where the Xbox One chews threw 18W compared to Sony’s 8.8W.
Since both consoles are expected to spend much of their time in this
mode, the Xbox One ends up actually
using more electricity than Sony’s system. In other words, the PS4′s
higher performance and power consumption in gaming is more than offset.
Image by NRDC
Improving energy efficiency
Where I think the NRDC goes wrong, however, is to assume that this generation’s console power consumption
will only improve by 25%. The report also makes some rather questionable assertions about charging power on the PS4.
For
starters, let’s talk about that 80-90W Blu-ray decode consumption on
both consoles — that’s ridiculous. It made sense for the PS3 to draw
that much power because Nvidia’s video decode block doesn’t appear to
have been capable of full video offload, which meant the Cell processor
was likely handling some of the task as well. AMD’s video decoder, in
contrast, can handle the entire process with relatively little effort
and for a fraction the power.
Here’s what this suggests: All of
the optimization work that went into the Xbox One and PS4 went into
making them run properly, with comparatively little tuning for low-power
operation when playing video. If you think about it, this makes sense.
Load balancing and figuring out which parts of the SoC can be
deactivated without impacting the user experience takes a great deal of
testing compared to flipping a switch and running full out. Future
updates should be capable of improving this by more than the 25% the
NRDC estimates. I’d hope for something more along the lines of 40-50W.
The
report goes a bit off base when it suggests that Sony must improve
battery charge efficiency, noting that “Sony’s PS4 uses 8 watts of power
in connected standby when USB charging is enabled… laptops perform this
function for only 1 watt.” Presumably this is when a device is actually
plugged in and charging. Unless there’s an enormous low-level software
issue, this has more to do with charge speed than charge time. You
cannot draw 1W from the wall and charge a device as quickly as you can
drawing 8W from the wall unless Sony deliberately used a charger with
miserable efficiency. Even if it did, fixing it would take a hardware
swap.
Finally, there’s the cost figure. The NRDC expects that
running your Xbox for five years will cost $150. “Enough to buy two or
three new games!” We are further told that consoles could use as much as
500MW of power, or the entire power consumption of Houston.
Total generating capacity of the United States? Approximately 1TW. What percentage of 1TW is 500MW? That’s just 0.05%.
So,
to put this in perspective, yes, consoles draw power, and yes,
consumers should be aware of that. But while consumer use of resources
is an important part of the US total, it’s only a modest amount. In
2011, residential use accounted for 22% of total power, compared to 28%
for transportation, 31% industrial, and 19% commercial. Furthermore,
since many console buyers will be previous owners of other consoles who
will presumably retire those devices, the net impact on US energy
consumption due to console production will be negligible.
We still
want to see Sony and Microsoft improve the power consumption of their
products, but don’t buy the fear-mongering. If you retire a PS3 or Xbox
360 and replace it with the modern version, the impact on your power
bill is going to be a few dollars per month, at most.
