The short version
What are the options for charging an Apple macbook air without using mains power or a fuel generator?
The longer version
I am travelling to a remote property and need to charge my Macbook air several times over a 2-3 week period. The place has a 12 volt set up to run various things. Engel fridge, lights, small fan etc. I will also have access to whatever charging options are available in a 2009 vehicle.
You can get a cigarette lighter inverter. I’ve had one in the past that will run power from car that Macbook Pro can connect to.
i.e. 150W (450W Surge) 12VDC to 240VAC Inverter with USB | Jaycar Electronics
Just don’t use it without car running! 
Thank you. I am going to go with purchasing the inverter you suggested.
I have since found out that the property owner has a cigarette lighter socket on the 12 volt solar set up. So it appears that I will be able to plug this new inverter into that, instead of the car cigarette lighter.
Cheers.
Works fine ‘not running’ when you’ve got a dual battery setup where one is isolated and deep cycle (lots of 4 wheels drives are set up this way).
I’ve used my laptop for days when camping like this (in combination with LED camp lights) before I needed to hook up the solar panel to top up the deep cycle battery.
A friend mentioned a sinewave inverter today as being a safer charging option for sensitive equipment. Not sure if this is overkill or not.
Pure Sine is much better than simulated Sine, but for your application a proper 12V DC power adaptor is likely more efficient than going 12V > 240V > 16.5V (or whatever the MacBook actually takes in the end).
A 12V > 240V inverter is handy if you have other devices you might want to use, but if it’s really only for the MacBook I’d go for a dedicated adaptor.
Thank you The_Hawk.
When you say a ‘dedicated adaptor’ are you referring to a genuine Apple product?
Cheers.
I don’t believe Apple sell a genuine 12V adaptor, so you’re stuck with aftermarket from fleaBay or similar.
I’ve never used or bought one myself, but here is an example of one of the first ones I saw on eBay:
Thank you.