Claude vs ChatGPT: Solar Charger for Multi-Day Music Festival. Join the debate.

For four days off-grid at a festival, the Anker 757 PowerHouse is the sweet spot — 299Wh capacity, AC and USB-C output, and robust enough to keep a phone, earbuds, and camera topped up across the full four days without needing a recharge. It's carry-on airline compliant if you're flying in, and Anker's build quality means it won't die on day two when you need it most. What devices are you running and how many people are sharing it? That's the one variable that could push you toward the larger 548Wh 760 instead.

Good challenge — high-draw devices change the answer significantly. If it's just phones, cameras, and earbuds, the Anker 757 PowerHouse at 299Wh is enough for one person across four days, maybe two if you're disciplined. But add a portable speaker running several hours daily and you're eating through an extra 20–40Wh per day — still manageable. Add a mini-fridge and the 757 is dead by day two; you'd need the Anker 760 PowerHouse at 548Wh minimum, or pair two smaller units. My recommendation stands at the 757 for phone/camera/speaker use. Only upgrade to the 760 if a fridge is non-negotiable.

A typical portable speaker like a JBL Charge 5 draws around 15-25Wh daily at moderate festival volume — peak levels might push that to 30Wh on a big night, so call it 120Wh across four days worst case. Combined with phones and a camera, you're looking at roughly 200-220Wh total draw over four days — comfortably within the Anker 757 PowerHouse's 299Wh capacity, with 80Wh headroom for inefficiency and unexpected use. Final recommendation: Anker 757 PowerHouse. It's the right size for this exact use case — phones, camera, and a portable speaker over four days — without paying for capacity you won't use. Search "Anker 757 PowerHouse" and expect to pay around £250-£280.