Solar Hacks

194 Articles

A solar inverter that asks for a password on its display

Decompiling Software To Fix An Old Solar Inverter

October 20, 2022 by 16 Comments

It’s a fact of life that electronic devices become obsolete after a few years. Sometimes this is because technology has moved on, but it can also happen that a perfectly functional device becomes near-useless simply because the original manufacturer no longer supports it. When [Buy It Fix It] found a pair of second-hand Power-One Aurora solar inverters, he ran into an issue for which he needed access to the service menu, which happened to be password-protected. The original manufacturer had ceased to exist, and the current owner of the brand name was unable to help, so [Buy It Fix It] had to resort to reverse engineering to find the password.

Thanks to the Wayback Machine over at the Internet Archive, [Buy It Fix It] was able to download the PC software bundle that originally came with the inverters. But in order to access all features, a password was required that could only be obtained by registering the unit with the manufacturer. That wasn’t going to happen, so [Buy It Fix It] fired up dnSpy, a decompiler and debugger for .NET programs. After a bit of searching he found the section that checked the password, and by simply copying that section into a new program he was able to make his own key generator.

With the service password now available, [Buy It Fix It] was able to set the inverter to the correct voltage setting and hook it up to his solar panels. Interestingly, the program code also had references to “PONG”, “Tetris” and “tiramisu” at various places; these turned out to be Easter eggs in the code, containing simple versions of those two games as well as a photo of the Italian dessert.

Inside the software archive was also another program that enabled the programming of low-level functions within the inverter, things that few users would ever need to touch. This program was not written in .NET but in C or something similar, so it required the use of x32dbg to look at the machine code. Again, this program was password-protected, but the master password was simply stored as the unencrypted string “91951” — the last five digits of the manufacturer’s old phone number.

The inverter was not actually working when [Buy It Fix It] first got it, and his repair video (also embedded below) is also well worth watching if you’re into power electronics repair. Hacking solar inverters to enable more features is often possible, but of course it’s much easier if the entire design is open source.

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Ebike Charges In The Sun

October 16, 2022 by 38 Comments

Ebikes are slowly taking the place of many cars, especially for short trips. Most ebikes can take riders at least 16 kilometers (10 miles) without too much effort, at a cost that’s often a single-digit percentage of what the same trip would have been with an internal combustion engine. If you’re interested in dropping the costs of your ebike trips even further, or eliminating it entirely, take a look at this small ebike with integrated solar panels.

While any battery can be charged with a sufficiently large array of solar panels and the correct electronics to match the two systems together, this bike has a key that sets it apart from most others: it can charge while it is being used to power the bike. Most ebikes don’t have charging enabled during rides, so if you want to use the sun while riding to extend the range of the bike you’ll need to find one like this. This bike uses two 50 W panels on the two cargo areas of the bike, attached to a 400 W MPPT charge controller. The Lectric XP 2.0 ebike has a motor with a peak rating of 850 W, but in a low pedal-assist mode the solar panels likely output a significant fraction of the energy used by the electric drivetrain.

Even if the panels don’t provide the full amount of energy needed for riding around, the project’s creator [Micah] lives in Florida, so just setting the bike outside in the sun for six to eight hours is enough to replenish most of the battery’s charge. It’s probably not going to win any solar-powered bike races anytime soon, but for an efficient, quick bike to ride around town it’s not too shabby.

Solar Flare Quiets A Quarter Of The Globe

September 18, 2022 by 13 Comments

In the “old” days, people were used to the idea that radio communication isn’t always perfect. AM radio had cracks and pops and if you had to make a call with a radiophone, you expected it to be unreliable and maybe even impossible at a given time. Modern technology,  satellites, and a host of other things have changed and now radio is usually super reliable and high-fidelity. Usually. However, a magnitude 7.9 solar flare this week reminded radio users in Africa and the Middle East that radio isn’t always going to get through. At least for about an hour.

It happened at around 10 AM GMT when that part of the world was facing the sun. Apparently, a coronal mass ejection accompanied the flare, so more electromagnetic disruption may be on its way.

The culprit seems to be an unusually active sunspot which is expected to die down soon. Interestingly, there is also a coronal hole in the sun where the solar wind blows at a higher than usual rate. Want to keep abreast of the solar weather? There’s a website for that.

We’ve pointed out before that we are ill-prepared for technology blackouts due to solar activity, even on the power grid. The last time it happened, we didn’t rely so much on radio.

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Hackaday Prize 2022: Compact Solar Tracking System Doesn’t Break The Bank

August 28, 2022 by 33 Comments

If you need to squeeze every available watt out of a solar panel, you’ll probably want to look into a solar tracking system. Unfortunately, they are usually quite large, heavy, and expensive. As an alternative, [JP Gleyzes] has put together a DIY solar tracking system that aims to address these issues.

Starting with a 100 W flexible solar panel purchased during a Black Friday sale, [JP] first created a simple frame using 20 mm PVC tubing and a few 3D printed brackets. It mounts on a wooden base with a printed worm gear rotation mechanism, powered by a stepper motor. The tilt is a handled by a lead screw made from a threaded rod, connected between the wooden base and the top of the solar panel, and is also driven by a stepper motor.

For even more efficiency, [JP] also created an MPPT charge controller with companion app using an ESP32, modified 20 A buck converter, and current sensor module. The ESP32 also controls the stepper motors. The optimum angle for the solar panel determined using the date, time, and the system’s GPS position. [JP] had also created a simple Android app to calibrate the panels’ start position.

This project is a finalist in the Planet-Friendly Power challenge of the 2022 Hackaday Prize, and all the details to build your own are available on your project page. Looking at the size of the system, we suspect future iterations could be even smaller.

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Dead Solar Panels Are The Hottest New Recyclables

July 19, 2022 by 99 Comments

When it comes to renewable energy, there are many great sources. Whether it’s solar, wind, or something else, though, we need a lot of it. Factories around the globe are rising to the challenge to provide what we need.

We can build plenty of new solar panels, of course, but we need to think about what happens when they reach end of life. As it turns out, with so much solar now out in the field, a major new recycling industry may be just around the corner.

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A Solar Frame From Scratch

June 6, 2022 by 14 Comments

“From scratch” is a bit of a murky expression. How scratchy does it get? Are you just baking your bread yourself or are you growing your own wheat? Rolling your own solar installation probably doesn’t involve manufacturing your own photovoltaic cells. But when it comes to making the frame to hold your panels, why not machine your own brackets and harvest the wood from trees nearby?. That’s what [Kris Harbour] did with his over-engineered 8.4kW solar stand.

He already had a wind turbine and a few solar panels elsewhere on the property, but [Kris] wanted a bit more power. At the start of the video, [Kris] makes an offhand comment that he wants this to last 30-40 years at a minimum. Everything from the focus on the concrete footings to the oversized brackets and beams reflects that. The brackets were cut on his plasma CNC and the wood was cut to rough dimensions using a sawmill on his property. He admits that the sapwood will rot away a bit after 20ish years, but since the core of the posts is heartwood, structurally they’ll last a long time. After planing down to the right size, cutting hole and grooves was a bit of an involved procedure. The structure is quite tall once erected and we loved watching it come together. The most impressive thing here is that this structure was put together by just a single person. All the rafters were cut and hand-chiseled to the right sizes and hoisted into place. The panels ultimately weren’t delivered on time and he had to switch to using new panels rather than the used panels he was expecting.

Previously, [Kris] had shown off his impressive hydroelectric setup. We’re looking forward to seeing the new solar array power all the projects [Kris] is planning in the future. Video after the break.

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the algae panel

Move Aside Solar, We’re Installing An Algae Panel

February 7, 2022 by 58 Comments

[Cody] of Cody’sLab has been bit by what he describes as the algae growing bug. We at Hackaday didn’t know that was a disease floating around, but we’ll admit that we’re not surprised after the last few years. So not content to stick to the small-time algae farms, [Cody] decided to scale up and build a whole algae panel.

Now, why would you want to grow algae? There are edible varieties of algae, you can extract oils from it, and most importantly, it can be pumped around in liquid form. To top it off, all it needs is just sunlight, carbon dioxide, and a few minerals to grow. Unlike those other complicated land-based organisms that use photosynthesis, algae don’t need to build any structure to hold themselves up or collect sunlight; it floats.

The real goal of the algae is to build a system known as “Chicken Hole.” The basic idea is to have a self-sufficient system. The algae feed the insects, the insects feed the chickens, and so on up the chain until it reaches [Cody]. While glass would make an ideal material for the algae tubes, plastic soda bottles seem like a decent proxy for a prototype and are much cheaper. He connected around 100 half-liter bottles to form long tubes and a PVC distribution system. The algae needs to be pumped into an insulated container to prevent it from freezing at night. At first, a simple timer outlet controlled the pump to only run during the day, draining it via gravity at night. However, the algae can’t heat up enough when running on cloudy, cold winter days, and it cools off. A solar panel and a temperature sensor form the logic for the pump, with a minimum temperature and sunlight needed to run.

[Cody] mentions that he can expect around 10 grams of algae per day on a panel this size in the winter. He’s going to need quite a few more if he’s going to scale up properly. Perhaps in the future, we’ll see panels growing algae robots? Video after the break.

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