Laptop displays are notorious for draining batteries. Intel may have a solution

Laptop battery life keeps getting better. More efficient processors have made a huge impact on how long our laptops last away from the wall plug over the past few years.

But that doesn’t mean we’re satisfied. We want our laptops to last a full working day and then some. We want to get our work done and have time left over for some Netflix. Intel gets that, and so it’s attacked one of the biggest power draws of all. The display.

Intel has partnered with Sharp and Innolux to develop a new laptop display technology that aims to cut power use in half. The coolest part? It might already be used in the laptop you’re using today.

Record-breaking battery life

Every time you fire up your laptop, several components go to work – meaning they start sucking power. If you happen to be on your laptop’s battery, it determines how long you can work or play before everything goes dark.

In fact, the average 13.3-inch laptop uses between five to eight watts of power all the time, of which two watts are consumed by the average display. If Intel wanted to further reduce power consumption and improve battery life, the display was an obvious candidate for innovation. The goal? Reducing the two-watt power draw down to one.

The company, therefore, put its Ecosystem Acceleration Group to work in searching out a solution. The result was a collaboration between Intel, Sharp, and Innolux in devising what it calls an Intel Low Power Display Technology (LPDT) with the objective of cutting LCD power consumption by half. According to Intel, LPDT is expected to deliver up to eight hours of additional local video playback – and up to 28 hours of battery life on select laptops.

So far, a handful of manufacturers have signed up to utilize Intel’s LPDT 1-watt display. HP was among the first with its Spectre Folio 2-in-1, but other laptops include the Razer Blade Stealth, the HP Spectre x360 13-inch (2019), and the Asus ZenBook S UX391UA.

The HP Spectre Folio was the first one to catch our eye. Back in December 2018, we reviewed the HP Spectre Folio and gave it a highly recommended review. Not only did we love the Folio’s leather-bound chassis and unique 2-in-1 configuration, we also praised its long battery life. It wasn’t just good. It was record-breaking good. We’re talking over 17 hours of 1080p video playback. Outside of the Surface Book 2, which uses a second battery in the tablet, the Folio is the champion in this particular test. All that with just a 54 watt-hour battery.

Intel and its partners have developed a secret sauce of hardware and software to make battery life like that possible.

From the smartphone to the laptop

The major innovation utilized by LPDT in reducing power consumption was the adoption of Low-Temperature PolySilicon (LTPS) LCD technology. It’s been used in smartphone displays, but now it’s coming to larger laptop panel sizes. Intel worked with its OEM partners to aggregate demand and make the technology cost-effective for use in mainstream laptops.

But, that’s not all. These low-power displays have intelligent hardware and software that combine to contribute around 20 percent of the total power savings. These capabilities include optimizing refresh rates, tuning the VESA standard with embedded DisplayPort connectivity, and an intelligent algorithm that manages things like brightness, colors, and filters for optimal performance and display quality.

The result is a total display package that draws around one watt during normal use. Overall, the LPDT display should operate with 30 percent to 50 percent less power than the typical 2-watt Full HD panel regardless of use case. While the LPDT 1-watt display will pull up to 1.6 watts of power when it’s operating at extremely high brightness (up to 400 nits), it still uses less power than a 2-watt display at similar brightness levels. Intel estimates that typical displays will draw between 40 percent to 100 percent more power in similar situations.

So, yes — this display technology totally works and is already being used in laptops in the real world. But that doesn’t mean it’s perfect quite yet.

So far so good, but room to grow

In order to demonstrate the low-power display technology’s effect on battery life, we conducted an informal A/B test. Specifically, we ran two versions of the Spectre Folio – one with the 1-watt display and one with a 2-watt display – through our suite of battery tests, side by side. Both units used the same Intel Core i7-8500Y processors and both were equipped with Intel LTE radios (but all tests were run on Wi-Fi). The only hardware difference between the laptops, other than the display, was RAM: The 1-watt display version had 16GB while the 2-watt display version had 8GB.

The results were illuminating. First, the 1-watt Folio looped our local test Avengers trailer for 1,067 minutes while the 2-watt Folio ran the same test for 938 minutes. That’s a difference of 129 minutes, or over two hours. Next, the 1-watt video ran for 676 minutes in our web browsing test while the 2-watt video ran for 614 minutes – a difference of 62 minutes. Finally, our CPU-intensive Basemark web benchmark test was essentially a draw, with the 1-watt version running for 301 minutes and the 2-watt version running for 287 minutes.

According to HP’s testing, the LTE-enabled Folio with a 1-watt display should play a local video for 90 minutes longer than an LTE-equipped Folio with a 2-watt display. Thus, our video results exceeded HP’s estimates. Also, HP estimates that without LTE, a 1-watt Folio will loop a local video for 165 more minutes than a similar Folio with a 2-watt display.

In short, our tests support the technology’s ability to improve battery life. At least, it does so long as the display is the most important power-drawing component. Stress the CPU and all bets are off. And at the same time, the 1-watt display looked just as good as the 2-watt display.

We’ll note that the Razer Blade Stealth, which uses this same technology, had noticeably mediocre battery life. In fact, it was one of our primary criticisms with that laptop. There are other factors involved, such as the inclusions of a higher-wattage discrete graphics card, but those results showed us that the 1-watt panel can’t overcome other deficiencies.

Who doesn’t want some extra battery life?

The LPDT display isn’t yet demonstrating quite the longevity that Intel is aiming for, at least not in our experience. Nevertheless, there are some real power savings when playing video and browsing the web, which likely reflects the most longevity impact from the display alone. An extra hour or two (or maybe more) of battery life isn’t anything to sneeze at.

We suspect that further optimizations will improve the performance of existing laptops like the Folio and achieve even greater results with other laptops. We certainly hope to see the savings increase in the future, especially in a wider variety of use cases. But for now, it’s clear that Intel’s onto something here.