SOLAR TECHNOLOGIES FOR AGRI-BUSINESSES Gerry Flores Photovoltaic Engineer, Energy Innovation Manager NSW FARMERS ASSOCIATION 15/11/2014 This activity received funding from the Department of Industry as part of the Energy Efficiency Information Grants Program. The views expressed herein are not necessarily the views of the Commonwealth of Australia, and the Commonwealth does not accept responsibility for any information or advice contained herein.
Electricity and gas price hikes are driving adoption of renewable energy 35 30 Average residential electricity costs ($c/kWh) 25 20 15 10 5 0 Jan-00 Jul-00 Jan-01 Jul-01 Jan-02 Jul-02 Jan-03 Jul-03 Jan-04 Jul-04 Jan-05 Jul-05 Jan-06 Jul-06 Jan-07 Jul-07 Jan-08 Jul-08 Jan-09 Jul-09 Jan-10 Jul-10 Jan-11 Jul-11 Jan-12 Jul-12 Jan-13 Jul-13 Jan-14 Weighted Average for All Capital Cities Melbourne Brisbane Adelaide Perth Hobart Darwin Canberra Sydney 8 per. Mov. Avg. ( Weighted Average for All Capital Cities)
Farmers have been at the forefront of solar PV uptake Average solar penetration in Australia is 22% In rural and regional areas the average is 29% Average solar penetration Number of PV systems installed Number of dwellings across across Australia (%) 35% Australia (%) 32% 31% 28% 30% 27% 25% 23% 20% 18% Rural and 15% regional Capital cities 32% and urban Rural and 10% 58% regional Capital cities 42% 5% and urban Other 68% 0% 0% Other Rural Regional – High Regional – Low Major Urban – Major urban – Non-Capital City Capital City Other 0% Capital cities and urban Other Rural and regional Capital cities and urban Other Rural and regional Sources: RECAA www.recagents.asn.au/wp-content/uploads/2014/04/GET-Postcode-report-for-RAA-April-2014.pdf
Effective steps towards energy management Renewable energy Energy efficiency Energy conservation and time of use management Energy analysis
Types of solar systems for farm businesses Integrated PV systems Grid-connected PV systems Stand-alone PV systems Water pumping -> stock and domestic & irrigation Solar-hot-water
Solar Cells Energy from photons (in sunlight) is absorbed by a semiconductor material by ‘knocking’ electrons loose from their atoms Electrons are then ‘collected’ and due to the composition of solar cells, they can only flow in one direction. This generates DC electricity. To generate a useful level of electricity, multiple cells are stringed together in individual solar panels, and multiple panels, and other power electronics such as inverters are used to condition the generated electricity into the appropriate current (AC or DC) and the required voltage levels. These components constitute a photovoltaic (PV) system.
Types of Solar Cells/Panels Crystalline silicon Mono-crystalline -> more efficient, more expensive Multi-crystalline -> almost as efficient, less expensive Mainstream thin film technologies Amorphous silicon -> less efficient CdTe -> Utility scale only Emerging CIGS Organic solar cells Perovskite cells
Solar irradiance The levels of solar irradiance changes throughout the day and year Mornings and afternoons have lower levels Summer has higher levels than winter kW-> unit of power kWh -> unit of energy Solar radiation power is measured in kW/m² Solar radiation energy is measured in (kWh/m²). 1 kWh/m² is also known as 1 Peak Sunshine Hour (PSH)
Grid connected systems Most common type of system 3 GW+ installed across Australia 56.4% average yearly growth over the last 10 years Oil 1.8% Gas Other fossil fuels 20.5% 0.8% Hydro Brown coal 7.3% 19.1% Renewables Solar PV 13.1% 1.5% Bioenergy 1.3% Wind 2.9% Black coal 44.8%
Grid connected systems Key energy saving opportunity for: Intensive animal farms Intensive producers, horticulturists Businesses with equipment running year-round (cool rooms, grain mills, frequent irrigation)
Grid-connected solar – Design Factors Solar resource Use Clean Energy Regulator’s (CER) ‘Postcode zones for solar panels’ for general planning Estimated yearly kWh Average generation per day Zone generated /kWp installed (kWh) 1 1,622 4.44 2 1,536 4.21 3 1,382 3.78 4 1,185 3.24 http://ret.cleanenergyregulator.gov.au/ArticleDocuments/205/RET-sgu- postcode-zones_0312.doc.aspx
Grid-connected solar – Design Factors Placement and orientation of PV panels Orientation – Optimal for a system in the southern hemisphere is facing north, however: Further eastward orientation can increase generated power in the morning Further westward orientation can increase generated power in the evening Tilt-A tilt equal to the location’s latitude will result in the greatest annual power output. A lower tilt (flatter) will increase power generated during summer An increased tilt (steeper) will increase power generated during winter
Grid-connected solar – Design Factors Placement and orientation of PV panels Mounting - Cheapest mounting option is on a fixed tilt & orientation on a roof Ground mounting is sometimes required and will increase costs. Single or double axis tracking can improve generated power by 10-25% but the cost premium and maintenance requirements typically outweigh this additional benefit.
Grid-connected solar – Design Factors Sizing
Grid-connected solar - Pricing Appropriately sized systems have a simple payback rate of 3-6 years Internal rate of return of 20% or more Pricing trends can be accessed online: solarchoice.net.au/blog/?s=pv+price+index Calculators also available to help estimate payback http://www.solarchoice.net.au/blog/solar-power-system-payback- calculator
Stand-alone systems Consists of a solar system that is not connected to the electricity grid Use energy storage technologies (batteries, water tank) Permits availability of power on cloudy days, nightime Must compare financial feasibility with cost of alternatives: connection point to the grid a diesel/petrol generator Typical financially prudent system will use solar + small battery bank + diesel genset backup
Stand-alone systems Key energy management opportunity for: Isolated homesteads Sheering sheds Watering points with no grid connection
Solar water pumping for stock and domestic purposes Solar systems can provide pumping power throughout they year When designed properly, they can give a steady and reliable water supply Solar pump replaces petrol driven pump in Southern NSW (photo courtesy of Solar Online Australia, GSES)
Solar water pumping for stock and domestic purposes A typical solar powered stock or domestic pumping system includes a solar array system controllers (for the array and the pump), an electric motor, and a water pump that moves the water from a source to its delivery point, typically a storage tank.
Solar water pumping for stock and domestic purposes There are multiple benefits of solar pumping systems over conventional systems Cutting bills for mains electricity and diesel Operate independently and reliably in isolated locations If fully replacing mains electricity, removes need for connecting power lines and poles If replacing diesel, removes noise, fumes and fuelling runs Easily scalable – add more panels to increase output Flexible - can be integrated with mains electricity supply Fewer breakdowns and less maintenance. Protection from rising energy costs
Solar water pumping for stock and domestic purposes – Design Factors Design process is involved Key step is to determine daily and seasonal water requirements and fluctuations throughout the year Size of pump and array can then be determined
Solar water pumping for stock and domestic purposes – Design Factors Full details are covered in our ‘Solar PV pumping guide’ (launching soon) And to be presented in future webinar Software provided by ‘Mono’ can be used to help design systems: www.solarcass.com
Solar water pumping – Irrigation Viable for stable year-round irrigation requirements: Blueberry (L/day per plant) Horticulture (orchards) 5 4 Drip irrigation 3 Blueberry (L/day 2 per plant) 1 0 M… A… Jan Feb may June July Aug Sept Oct Nov Dec More challenging on a cost basis for crops which requiring large amounts of water in isolated events The water requirements of a cotton crop with an irrigation scheme that runs for approximately six months of the year (Source: WATERpak, Cotton Research and Development Corporation).
Solar water pumping – Irrigation
Solar water pumping – Irrigation Cost breakdown of solar pump design for large irrigation system
Solar-hot-water Widely deployed on Australian farms Can provide all or a large portion of the energy needed for water heating. Works in conjunction with an electric or natural gas “booster,” to provide additional heat and maintain desired temperature points for stored water. It is a key energy saving measure for: Residences or worker accommodation Dairy farms (high temperature water is used to wash equipment after milking)
Recommend
More recommend
