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Two Dam Sustainable

Lead Sustainability Consultants | Sustainability Project Manager | Hybrid Renewable System Architecture Design | Green Building Accredited Professional (Green Star SA Net Zero Carbon certification management)

Two Dam Sustainable, a trout farm near Montagu, Western Cape, is one of the first four pilot projects to have been certified net zero in South Africa in October 2017. As the sustainability consultant on the project, Ecolution worked closely with the farm as the sustainability project manager, and were appointed as the Commissioning authority that certified the farm net zero under the GBCSA’s Green Star SA Net Zero Carbon certification.  

Operating as an off-grid, responsibly operated trout farm, it produces ethically made trout products and runs almost entirely off of renewable energy. The majority of the energy used for the farm is provided by a 31 kW photovoltaic panel array and a ‘high pressure, low water volume’ micro-hydro turbine that generates up to 1kW of continuous electricity.

The farm is home to a hyper-efficient Recirculating Aquaculture System (RAS) – which is the first of its kind in Africa. The Rainbow Trout RAS operates sustainably by being an energy efficient low head recirculating system which requires comparatively low electricity as opposed to conventional high pressure RAS or high volume raceway cultures, which require and often pollute huge volumes of fresh water. 

Project Initiatives
  • PV – feeds consumption directly and
    charges batteries for night time (PV 31.15kWp)
  • Hydro Electric – minimal and feeds directly
    into the batteries (Hydro 1kWp)
  • Carbon offsetting for all LPG generator use
  • 100% LED lighting
  • Predominantly solar thermal hot water
    generation
  • Buildings are all naturally ventilated
  • Energy efficient appliances (Energy Star
    Rated or A+)
  • Cool roof paint
  • Renewable energy from PV and Hydro is
    carbon neutral
  • Total non-renewable energy produced:
    5572.1 kWh = 35.36 GJ LPG per annum
  • Total Carbon Offset: 8,478.75 kg CO2-e
    (figure accounts for wastage and efficiency
    losses)
Project Obstacles
  • Remoteness and related logistics and
    coordination difficulties which also resulted in
    cost increases
  • Dependence on consistent and reliable
    electricity for the farming operation
  • Lack of water (hydro) – drought is impacting
    on the availability of water and the output of the
    micro-hydro turbine
  • Finding a suitably qualified and reliable
    supplier/installer for a complete hybrid off-grid
    system in an industry with little experience in
    such a unique application
  • High initial funding requirement for the
    off-grid energy system
  • Difficult to quantify remaining carbon
    impact
Project Wins
  • Eventually finding a suitable and qualified
    installer
  • Saving electricity – and associated costs and
    environmental impact
  • Avoiding the need to invest in installing
    and securing a mains grid connection from 7km
    afield
  • Being independent of the grid
  • Able to justify and source the required
    funding
  • Contributing to a ‘worthy’ and reputable
    carbon offsetting project
  • Doing the right thing 
  • Neutralising all negative effect of our
    energy consumption