Walipini Resources; A Plan In The Making

I've heard about a Walipini a while ago, however I've never taken the time to look into it.
The following is a few links put together as resources for northern structures, as we are in rural Saskatchewan - it gets quite cold up here... Like -30 average cold, blowing wind often.

First thing's first - heat source. I've decided if we build a walipini we're going to need a rocket mass heater, possibly coupled with some thermal mass in the ground. I was possibly thinking some sort of connection to the house's power but unfortunately our power goes out a couple times a month, and in -40 heat tends to dissipate quickly, so we'll need something reliable and off the grid. We currently do not have finances to be able to buy a proper solar power system, so rocket mass heater it is:

https://vergepermaculture.ca/2013/01/29/finishing-the-rocket-mass-heater/

I've currently been looking at other designs - to see what is financially suitable for our budget, which basically consists of scrap materials we could get our hands on or off off kijiji.
Here are a few examples of walipinis in northern regions I have found:

https://vergepermaculture.ca/2013/12/18/robs-modified-walpini/
http://waldenlabs.com/5-northern-greenhouse-examples/

This one isn't a northern walipini but the concepts are there that will be applied:

https://www.ecowatch.com/300-underground-greenhouse-grows-your-food-year-round-1882129974.html
http://opensourceecology.org/w/images/1/1c/Walipini.pdf

It is suggested that a walipini be built against the house - particularly the south side not only to heat the house, but save money on materials. I'll have to draft a possible plan as the only spot This could be placed is the south west side of our house - there's a porch in the middle and septic on the south east.

A plan is in action.