Day 8

More research is needed. We want to charge laptops and phones, see what we’re doing inside Steve Shelter and run festive string lighting to Napoleon the pizza oven. And possibly make our own pizza sauce and smoothies. So we need to power a blender.

The battery powering the LED in our mini-Steve model put out 3.7V and we had to boost that to 5V to operate the LED light. The battery storing the energy from the full-size installation will put out 12V. So the question is: can we run all that on 12V or do we need to boost the current to 240V (which is what comes out of the sockets in our houses). In other words:

Do we need an inverter?

This breaks down to five questions that the team now sits down to investigate:

1. Can you charge a laptop on 12V current? Answer: Yes! In fact, that big block in any typical laptop charge lead works mostly to reduce the current to somewhere around 19V. The laptop battery itself usually operates between 11.1V and 14.8V, which is the same as the kind of car battery we will have. The extra volts allow charging the battery while using the laptop when you’re plugged into 240V. But we don’t need to worry about that. We will need to purchase a
2. Can you plug your usual USB phone charge cable into a 12V socket and charge your phone? Answer: Yes you can! Phones charge at 5V and that’s an easy drop from 12V. All you need is a little USB car charger that costs a few pounds.
3. Do 12V ceiling LED strip lights exist? Answer: Yes, they do. In fact there’s quite a range that can cope with outdoor living. So we can tick that box.
4. Are there 12V festoon lights? Again, yes – lots of them actually work on 12V and need an adaptor to plug into household 240V. Some are even designed to be plugged straight into a car battery!
5. Are there 12V blenders? Yes, yes there are, thanks to gastronomically gifted campers. However, reviews are a bit mixed. Pizza sauce and smoothies seem to work if the fruit is soft, but blending ice on 12 volts doesn’t seem possible. So if we want slush puppies, then we might get disappointed.

Slush puppies! Yes, of course we want slush puppies!

Who’d have guessed? Well, given the positive answers to questions 1-4 it’s probably not worth changing the whole system to 240V just because we want slush puppies. Later on, we can invest in an inverter that plugs into a 12V socket and has a socket for plugging in an ordinary domestic 240V blender.

Until then, there’s always the smoothie bike as a back-up!