Energy Savers
Southern Downs

Southern Downs Piggery

Proposed
35-48
Proposed Energy Savings
Industry
Intensive Animal Industries
Location
Southern Downs
Solution
LED Lighting, Solar Batteries, Hot Water, Ventilation Fans

Farm Profile

An energy audit at a Southern Downs piggery investigated electricity and gas consumption and has identified opportunities to significantly reduce costs.

The site farrows and weans pigs before transporting them to a larger site for finishing. The site has several sheds for different stages of rearing, two houses, a small office and two pumps.

Electricity Audit

The farm could save electricity onsite from recommendations in the audit being:

  • Upgrade lighting using new LEDs
  • Upgrade Ventilation fan
  • Reflective roof coating
  • Solar Bore pump with or without battery storage
  • Various solar P.V systems up to 100kW in size

With potential energy savings of 26,280kWh and a payback of less than a year the quickest way to improve efficiency onsite would be from the installation of new LED lighting.

Recommendation Energy Saving (kWh) Cost Saving Tariff 62 ($) Cost Saving Tariff 20 ($) Payback Period Tariff 62 (Years) Payback Period Tariff 20 (Years)
Upgrade lighting to new LEDs 26,280 10, 8,300 0.5 .6
Fan Upgrades 14,400 4,200 3,700 9.5 10.8
Reflective roof coating 7,500 3,000 1,800 >20 >20
Total 48,180 18,190 13,800 N/A N/A

 

Under current tariff 62 the cost savings of $10,990 per annum from the replacement of the lights could be utilised to install an adequate solar PV system. The audit considered a number of opportunities with relatively quick paybacks from the implementation of solar, including:

  1. Two smaller residential solar systems 1.5kW and 5kW
  2. Bore Pump: Solar only or Solar and batteries.
  3. Large scale solar systems of 30kW or 99.5kW
Recommendation Energy Savings (kWh) Cost Savings Tariff 62 ($) Cost Savings Tariff 20 ($) Payback Tariff 62 (Years) Payback Period Tarif 20 (Years)
Two Residential Solar Systems 7,930 3,700 2,300 2.4 3.8
Bore Pump: Solar only (Tariff 33) 10,990 1,600 N/A 4 N/A
Bore Pump: Solar and batteries (Tariff 33) 13,000 1,900 N/A 11 N/A
30kW Solar System 43,000 14,500 9,000 2.9 4.3
99.5kW Solar System 62,000 19,600 11,400 4.9 9.4

 

Assuming the bore pump is on load control tariff 33 an initial solar system is recommended to cover the load with this showing a four-year payback. Should battery pricing decrease, then the secondary option may be worth considering. It would be worthwhile to factor this in when designing a system using a battery capable invertor.

Solar systems greater than 30kW are subject to a more complex network connection process, so the installation of the 30kW system would prove beneficial at this stage. With a capital cost of $41,000 the audit recommended remaining on tariff 62 as the system shows a payback of 2.9 years. Moving to tariff 20 the payback for the 30kW system would increase to 4.3 years.  The farm will be required to move to Tariff 20 on 1 July 2021 when the Obsolete Tariffs cease.

Location Current Usage (kWh) Cost ($) Recommendation Energy Saving (kWh) Cost Savings ($)
Piggery 115,272 36,607 Lighting and 30kW Solar PV 26,280  43,000 5,500

14,500

Main Bore Pump 10,385 2,001 Solar PV only 10,900 1,600
Farmhouse 15,435 5,408 Solar PV 7,900 3,700
Total 141,091 44,016 N/A 88,080

>35% Saving

25,300

>40% Saving

 

Implementation of the recommendations at the piggery will ensure that the farm is able to remain a small electricity user and able to remain on small business tariffs.

Implementation of the above recommendations from the energy audit would significantly reduce the kWh and dollar costs per unit of output at the farm with new KPIs reduced.

Benchmark WEANED PIGS ANNUAL ENERGY Total (kWh) Annual Energy Cost ($) KPI (kWh/Weaned Pig) KPI                 ($Cost/Weaned Pig)
Pre-Audit 21,510 141,091 44,016 6.55 2.04
Post Audit (Gas Saving) 21,510 53,011 18,716 2.46 .87

 

From the table the farm could realise a 37 per cent reduction in energy consumption, and 42 per cent in energy costs per unit of output.

 

Gas Audit

The audit identified a number of cost-effective initiatives on site that could reduce gas consumption by 1,083GJ per annum including the items in the table below:

Recommendation Energy Saving (GJ) Cost Savings ($) Payback (Years)
Solar Hot Water (Farrowing Shed) 590 24,500 3.1
Temperature Control for Heat Mats 415 18,500 0.4
Insulation on Hot Water pipes 78 3,500 0.5
Total 1,083 46,500 N/A
Installation of Biogas 1,680 67,000 5.3

 

The audit considered the opportunity to the install a biogas facility capturing and recycling gas produced from the piggery. This would reduce the high costs attributed to LPG, though due to production numbers, biogas production is limited and is not recommended unless the piggery expands into the future.

At a cost of $400,000 and a potential payback of 5.3 years the biogas is a more long-term consideration depending on the future direction of the farm.

Implementation of the recommendations in the table above would significantly reduce LPG gas consumption and dollar costs per unit of output with new KPIs seen.

Recommendation WEANED PIGS (ANNUAL) ANNUAL GAS USE (GJ)  KPI (MJ/PIG)
Pre-Audit 21,510 2,102 0.097
Post Audit (General Recommendations) 21,510 1,019 0.047
Post Audit (Biogas) 21,510 422 0.019

 

The table shows the farm could achieve a 48 per cent reduction in gas consumption as a result of implementing the general recommendations. Should the farm capture and use biogas than a further 40 per cent reduction in LPG may be seen.

With LPG costs considerably larger than electricity, the farm should consider low cost, recommendations to allow additional capital expenditure to implement some of the larger energy saving measures.

The figures show there are significant electricity savings to be realised onsite leading to reduced KPIS.

An energy audit is a great way for a business to cut costs and boost productivity. Find out about what’s involved in an energy audit HERE and subscribe to our bi-monthly energy e-news HERE.

If you have any energy efficiency related questions for the team get in touch at energysavers@qff.org.au.