The Heating & Cooling
"Heating and Cooling" should probably be combined with lighting and ventillation and thrown under some other banner heading, like "environment management" or "living space control". Basically, the best building in the world is nothing more than a cave - and a dark one at that - unless you can manipulate the environment to make it more comfortable to be in.
The environmental condition in which most of the population feels "comfortable" is quite difficult to define and even more difficult to manage in an energy conscious and environmentally responsible way. The air needs to be fresh and moving, but not so much as to be noticable! It needs to be at the right temperature, with an acceptable temperature gradient from floor to ceiling. The moisture content (relative humidity) needs to be maintained within a narrow band. The radiant temperatures of the various surfaces need to be within a degree, or two, of the "ideal", otherwise we feel uncomfortable. Add to this catalogue of requirements the need to see clearly, but not suffer from glare, nor to waste vast amounts of energy on lighting unecessarily - the simple pendant light in the middle of the room, with a switch by the door looks very outdated. Which is precicely where the bimetallic strip thermostat that controls the heating should find itself - outdated! As for cooling - for most of us in the UK, that comprises nothing more complex than opening the window - which may well do more harm than good!
I find it quite amazing that we now expect air conditioning in our cars - however lowly the specification - yet apparently have no comprehension of managing our home environment to provide some degree of comfort!
The various systems employed at Bluebell Bungalow are summarised below and will be explained in more detail on the adjacent pages once time permits us to put them into words!
Shallow pilefield groundsource energy - Piles under the building used to source and sink energy to / from.
Water to water heatpump - Moves energy from one place (source) to another (sink), with an attendant shift in temperature to make the energy usable in "normal" systems.
Underfloor heating & cooling - PIpe matrix buried in the concrete slab (which acts as a huge thermal "battery"), used to heat and cool the living space.
Ground to air heat exchange - A big pipe (315mm diameter) with a special internal coating (silver atoms to combat microbial growth), buried 2m down under the drive. Feed it with air from the surroundings (+35C summer, -5C winter) and it pops out of the other end at 16C to 11C - all for turning a modest fan! (I'm guessing here, but 200W of fan is probably way too much and it's just done 50% of the energy demand!!)
Heat recovery ventillation - Passive system utilising plate to plate heat transfer to suck the energy (warmth / cool) from the stale air extracted from the bathrooms and kitchen, transfer that energy to the fresh incoming air from the Ground to Air system and push it into the various living spaces - bedrooms, lounge, etc.