Off-Grid Cottages and Cabin Solar Solutions

Off Grid Cottages and Cabins

The ability to generate enough power to run your off grid cottage or cabin is both affordable and realistic.

Three factors need to taken into consideration when designing an off grid system:

  1. Peak Power Consumption

    • the size and number of inverters needed to provide power is dependant on what you want to plug in – a fridge, 1/3 HP water pump. microwave oven, entertainment system and lights are the typical loads connected to an off grid system
    • having the fridge, water pump, flat panel TV, microwave oven and some lights running at the same time will draw approximately 3,000 watts of power
    • if the fridge, water pump both turn on when the TV, microwave and lights are being used, a 5 second peak load of 6,000 watts may be reached
    • the Conext SW 4024 inverter will provide 3,400 watts of continuous power; 4,000 watts of power for 30 minutes; 7,000 watts of power for 5 seconds – this is adequate for most cottages and cabins
    • if more power is needed a second inverter can be added to the system
  2. Daily Power Consumption

    • enough solar panels should be installed to generate in one day the amount of power consumed in one day
    • the average amount of power generated in one day will vary depending on the time of year
    • 4 250 watt panels facing due south will generate the following amount of power:
      Month Average Power Generated
      January 2.0 kWh/day
      February 3.0 kWh/day
      March 4.3 kWh/day
      April 4.1 kWh/day
      May 4.6 kWh/day
      June 4.6 kWh/day
      July 4.9 kWh/day
      August 4.1 kWh/day
      September 3.5 kWh/day
      October 2.6 kWh/day
      November 1.5 kWh/day
      December 1.3 kWh/day
      yearly average 3.4 kWh/day
    • if the average daily power consumption of a seasonal cottage (May to October) is 8 kWh, then 8 250 watt solar panels will generate enough power to satisfy this level of consumption
  3. Battery Bank Power Storage

    • since not every day will be sunny, it is necessary to store the excess energy generated when it is sunny
    • three days of autonomy is recommended for off grid cottages and cabins
    • for example, a daily average consumption of 8 kWh per day a battery bank capable of storing approximately 24 kWh of power is needed

Batteries

There are three types of lead acid batteries that are typically used in off grid systems: flooded lead acid (FLA); absorbed glass mat (AGM); tubular gel (TG).

  1. Flooded Lead Acid (FLA) Batteries

    • least expensive initial price
    • highest operating cost ($0.885/kWh/cycle)
    • need regular maintenance
    • will off-gas potentially dangerous gases
    • limited cycle life of 500 cycles (approximately 5 to 7 years)
    • can only be discharged to a depth of 50%
    • not recommended
  2. Absorbed Glass Mat (AGM) Batteries

    • high initial price
    • moderate operating cost ($0.345/kWh/cycle)
    • no maintenance needed
    • no off-gassing
    • moderate cycle life of 1000 cycles (approximately 10 to 14 years)
    • can be discharged to a depth of 80%
  3. Tubular Gel (TG) Batteries

    • highest initial price
    • lowest operating cost ($0.16/kWh/cycle)
    • no maintenance needed
    • no off-gassing
    • long cycle life of 2,500 cycles (approximately 20 to 25 years)
    • can be discharged to a depth of 80%
    • recommended

Typical Off Grid System

  • Conext SW 4024 120/240 VAC Inverter/Charger
  • Conext SW Universal DC Breaker Panel
  • Conext SW AC Breaker Panel (120/240 VAC)
  • Conext System Control Panel
  • Conext Battery Monitor
  • Conext C40 40 Amp Charge Controller
  • 8 300 Watt Solar Panels with Kinetic Solar Racking
  • SolaDeck Combiner Box
  • Armoured TECK Cable
  • Balance of Components
$7,700.00 + Installation + HST

Battery Bank Options

  • 4 2VRE5-3400TG – 6 volt 485Ah tubular gel batteries with a total capacity of 9.3 kWh capacity at an 80% depth of discharge; includes battery cables and interconnects
$4,040.00 + Installation + HST
  • 2 EV8DA-A – 12 volt 280Ah absorbed glass mat batteries with a total capacity of 3.4 kWh capacity at an 80% depth of discharge; includes battery cables and interconnects
$2,180.00 + Installation + HST
  • 4 EV8DA-A – 12 volt 280Ah absorbed glass mat batteries with a total capacity of 6.8 kWh capacity at an 80% depth of discharge; includes battery cables and interconnects
$4,150.00 + Installation + HST

Quotations for multiple inverter systems, larger solar arrays, top-of-pole mounted arrays, and larger battery banks are available on request.

Off Grid Homes

Off grid homes require larger systems than would be typically installed in a cottage or cabin.

  • multiple inverters to provide power to additional power draws, such as:
    • sump pump
    • furnace fan and control systems
    • washer and gas dryer
    • air conditioner
    • ceiling fans
    • kettle
  • larger solar arrays to provide enough power in November and December
  • larger battery bank to provide needed energy storage
  • back-up generator with automatic generator start module installed

Quotations for systems for off grid home are available upon request.