Bikes for transport, electrified xtracycles

I've written about bikes before. I first introduced my xtracycle here, the ebike and associated thinking here, and talked about cycling with two kids here.

As I introduced last post, if we want to lessen the destruction we cause to the biosphere, it can be hard to identify where to best focus. Here is the priority list (as I see it):

1. drive less or (preferably) not at all
2. eat less industrially-produced meat, fish and dairy
3. use less energy and buy GreenPower
4. buy less stuff

In terms of reducing environmental damage, I think these are the Big Four. It's also great to buy organic, go to farmers' markets, do gardening, and play acoustic guitar (we try and do all these) but if you drive across town to pick up your organic veg in your Pajero, it's of questionable benefit (in my opinion). To my mind, this is similar to the (well-intentioned) person with a drawer full of washable nappies, and a disposable nappy on their child.
This is the reason I haven't written much about the garden. We put a fair bit of effort in, but it seems to me in many ways the less important part of what we are striving for -- though that could be seen as my prejudice as an engineer! I'd love to hear people's thoughts/criticisms of this idea. I do plan to write about it though.

We have a car (a small SUV in fact!), and are exploring how little we can drive it (it has been about a fortnight since we drove). I'm keen to see whether we can share a car with some like-minded people nearby but we're yet to organise that. A difficulty is that my youngest child is under 3, and so we have many years of car seats ahead of us.

In terms of thinking about efficiency, 1 L of petrol is equivalent to about 10 kWh. That is extraordinary, and shows just how much energy a car is using (and just how energy-dense petrol is). This is a big reason I love bicycles.

I recently made some changes to our bikes. The xtracycle was on a bike that was really too big for my wife and I hoped that putting it on a smaller bike would let her use it more effectively. Also, we sometimes took the kids places quite far away (or up a decent hill) that was hard to pull the trailer. I hoped that combining the xtracycle with the ebike would solve all these problems.

The xtracycle, now with electric assist front wheel and disc brakes.

I also took the opportunity to alter the platform on the back (using some found material) and bring the child seat forward. This greatly helps the dynamics of riding it, as the kids' weight is now in front of the rear axle. I've also mounted the battery for the ebike beneath the rear tray. I'm yet to finish installing a front rack on the bike.

Performance

The bike rides well. It carries a rider and two passengers (front passenger sits on platform and holds rear-facing handlebars, rear child sits in the plastic seat). It has a huge luggage capacity. It is fast, and can easily be ridden at 25 - 30 km/h on the flat when fully loaded. Handling is greatly improved with the children's weight further forward. Because the rear wheel is now 26" instead of 27", the weight is also marginally lower, which also improves handling. At some point, I might consider replacing the rear wheel with a strong 20" or 24" wheel.
In its previous  configuration (here) I carried a child and about 100 kg of luggage on it. It's quite amazing how much weight it can bear!

The problem is that it is still relatively hard to ride with a child in the rear seat, and my wife is still uncomfortable. It requires a lot of upper-body strength to balance -- particularly when the rider is getting on/off with two kids on the back. I do think a smaller rear wheel would help this, but we may consider a bakfiets (or similar dutch bike) instead. Not sure at this point. Also, our oldest child is nearly at the point where he could ride a tag-along (he can ride his own bike 5 kms, so could probably do 15 km on a tag-along).

Conclusion

We use this bike a lot. It's good for two kids, and great for cargo. Also, there have been many times that the ebike has allowed us to leave the car at home. I believe that, if electric vehicles are the future, it will be electric assisted bikes for most people -- electric cars will remain too expensive for most.