Author Archives: Paul

USB-C Charging for Laptop Computers

Laptop computers are now being produced which use a USB Type-C connector to charge the laptop. Laptops need more power than phones or tablets, and the new USB PD protocol (PD = Power Delivery) makes much higher power levels possible; up to 100W can be passed over some USB-C cables. The USB specs and terminology keep getting revised and now contain a smorgasbord of optional features, and the marketing terminology is totally confusing. Here’s my summary of what you need to know about USB-C laptop charging, cables and chargers.

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Asus P3B LED Projector evaluation

The Asus P3B is a bright Mini LED projector rated 800 ANSI lumens with an internal 45Wh battery. I had the chance to test an Asus P3B portable projector briefly before it was sent off to it’s new owner in Africa. I measured it’s power consumption and did a short subjective evaluation of it.

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Minimize laptop energy consumption – Maximize battery life

When running your laptop computer on solar power, you should adjust your power-saving settings in Windows or Linux in order to conserve power when plugged in the same as it does when running on battery power, because your solar power isn’t unlimited the way an AC outlet is. Most laptops waste a lot of energy when recharging their internal batteries, so you’ll be most efficient with your limited solar energy if you keep the laptop plugged in and fully charged. However, keeping the battery constantly topped-off isn’t the best thing for the laptop battery. Continue reading →

When and how to choose a power bank

There are a lot of “power banks” on the market that appear to have similar capability to the Half-Pint we build and sell, but in practical use they are significantly different. Here’s how to choose and things to watch out for: Continue reading →

Portable Solar Power System Usage Scenarios

Are you really going to sit out in the sun next to your solar panel?

How you plan to use your solar power system affects what you need to buy, especially when it comes to the solar panels. Picture exactly how you’re going to use your system before you buy. Continue reading →

Solar Charging of LiFePO4 batteries

Compared to lead-acid batteries Lithium Iron Phosphate (abbreviated LiFePO4 or just LFP) batteries are simple to charge and quite forgiving about voltage set points. You can use most “12-V” lead-acid solar charge controllers to charge a 12.8 V LFP battery. On those with adjustable settings, here are our recommendations for voltage set-points and why.
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GTIS Power and Communications Systems

Technology for the ends of the Earth