Energy (& Renewable Resources)

Energy (& Renewable Resources)

1. Passive Solar (PS) Design

   • PS Aperture
     • Admission of sunlight
     • Glass 'entrance'
     • Facing direction of winter sun
   • PS Energy Control
     • Features controlling natural light/ heat
       • Overhangs
       • Sensors
       • Vents
       • Awnings
       • Blinds
       • Differential thermostat
   • PS Heat/ Energy Distribution
     • 'True' passive
       • Conduction
       • Convection
       • Radiation
     • Fans
     • Ducts
   • PS Absorber
     • Surface absorption
       • Later release
     • Hard, dark surface
   • PS Thermal Mass
     • Below absorber
     • Retains thermal energy
     • Materials
       • Concrete
       • Stones
       • Brick
       • Tiles
       • Water
         • Tanks need yearly treatment to avoid bacterial growth
     • Needs insulation from external heat
   • Trombe walls
     • Glass -> Air -> Wall
     • Wall heats air
     • Thermal mass radiates when internal temperature sub-optimal
   • Solar chimneys
     • Circulation of air via convection currents
     • Dark, matte surface
     • Tall & wide
     • Insulated from building

2. Geothermal

   • Vertical Loop
     • Used when soil too shallow for trenches
     • 400ft deep holes 20ft apart
       • Two pipes - connected with U-bend
   • Pond Loop
     • 8ft under source - supply pipe
   • Slinky Loop
     • More piping in a shorter trench
   • Horizontal Loop
     • Trenches 4ft deep at least
     • Two pipes

3. Home Energy Units

   • Tesla Powerwall
     • Mount on wall or floor
     • Water resistant & dust-proof
     • -20-50 degrees centigrade
   • Nissan xStorage
     • Cells can be made from old car battery cells
       • From Nissan LEAF
     • Between 0-30 degrees centigrade
     • Indoors
     • On a load-bearing wall
   • Powervault
     • Collects off-peak energy and solar energy
     • UK option
     • Needs ventilation clearance at back
     • 0-35 degrees centigrade

4. Concentrated Solar Power (CSP)

   • Dish/ Engine Systems
     • Solar concentrator
       • Tracks Sun
     • Power conversion unit
       • Receiver
       • Engine
   • Parabolic Trough
     • Reflecting mirror
       • Ag or Al generally used for backside of glass
     • Heat Collection Element
       • Metal covered with glass and vacuum or air between
         • Reduce heat loss
         • Metal tube coated with material
           • High solar radiation absorption
       • Needs to be efficient
     • Heat transfer fluid
   • Power Tower
     • Heliostats
       • Flat mirrors
       • Control system to follow Sun
     • Receiver