Automation Devisions
Technoserve designs, specifies, procures, installs, commissions and operates solar photovoltaic generation systems for industry.
Design
South Africa has the best solar irradiation that can be found worldwide.
Therefore, South Africa is the ideal place to harness power generation by photovoltaic technologies.
Photovoltaic (PV) modules generate power when photons from incident light displaces an excess electron from one molecule to a molecule
that is in need of an electron.
For an excellent description on how PV modules work, have a look here: https://www.youtube.com/watch?v=2AX0qvnjSnM
The following diagram depicts a typical grid-connection PV system:
Of course not all PV systems have to be grid-connected. Our clients’ requirements may be any of the following:
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Grid-connected system (with feed-to-grid or without)
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Grid-connected system with batteries for backup power
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Grid-connected system with diesel generator for backup power
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Off-grid system with batteries and diesel generator
Technoserve will design a PV system according to your requirements, taking into account the following:
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Optimum angle of the installation with respect to the sun
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Facility power demand, energy requirements and existing electrical infrastructure
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Available land/roof space
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Structural strength of the roof
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Any Power Purchase Agreements between Owner and Utility
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Optimum cable diameter and length
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Requirements for sufficient earthing as well as protection against lightning and induced surges
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Grid connection parameters
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Requirements for generation metering, remote monitoring of generation and system status
Based upon the optimum design, Technoserve will produce a proposal that will provide the following:
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Available solar resource for an entire year
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Possible Energy generation (kWh—kilowatt-hours)
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PV generator Performance-Ratio (see http://files.sma.de/dl/7680/Perfratio-UEN100810.pdf)
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Payback calculation based on typical forecasted energy generation and electricity savings, taking into account the accelerated asset depreciation for renewable energy generation facilities as allowed by the South African Revenue Services (SARS)
Specify and Procure
Technoserve uses PV system products that conform to the highest local and international standards.
Photovoltaic modules used are:
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TUV and UL certified
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Insulation class-II
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CE certified
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25-year generation lifetime
Solar PV inverters used are:
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TUV, UL and NRS-097-2 certified
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Grid-code compliant: anti-islanding, auto-synchronisation and set-up to operate on the South-African grid
Solar PV DC cables used are:
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Ozone resistant
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UV resistant
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Insulated up to 1000V
TUV and UL certified
Installation
The Solar PV system is installed according to SANS 10142:1.
If Medium-Voltage (3,3kV up to 33kV) connections are applicable then SANS 10142:2 will be applicable.
Technoserve MV is more than capable of effecting such connections: http://www.technoserve.co.za/lightbox/medium_voltage.htm
In South-Africa no solar PV installation standard currently exists but the SABS (South African Bureau of Standards) in association with industry
and Eskom, is currently working on the SANS 10142:3 standard that will govern these type of installations in future. Until this standard is promulgated, however, Technoserve uses the following standards, amongst others, as benchmark:
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SANS 10142:1 (Standard for low-voltage installations)
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SANS 10142:2 (Standard for medium-voltage installations)
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IEC 62548 (PV Array design requirements)
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IEC 61730 (PV module safety)
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IEC 61727 (Requirements for the Utility Interface)
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SANS 10160 (Basis for structural design and action for buildings and industrial structures)
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SABS 0162 (Structural use of steel)
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SA Occupational, Health and Safety Act
Technoserve will supply the applicable installation certificates required by law and the Utility, signed by a Professional Engineer, whom is registered in terms of the Engineering Professions Act of South Africa.
Commissioning
Technoserve does the installation right, the first time. We do so by ensuring that the latest testing practices are implemented from the start.
These include:
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Cable Megger testing
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Medium-voltage cable VLF testing, where applicable
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Infrared thermograph, see www.technoserve.co.za/lightbox/thermography.htm
and http://www.technoserve.co.za/lightbox/images/thermal/3_Thermography_on_photovoltaic_systems.pdf
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Earth-impedance test
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Protection system tests
The following commissioning standards, amongst others, are applicable:
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SANS 10142:1
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SANS 10142:2
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IEC 62446 (Minimum requirements for PV system testing)
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IEC 61727 (Requirements for the Utility Interface)
Operation
Depending on the requirements of the client, the PV Generation Facility can be designed to be remotely accessible via web-interface.
This will allow the Operator to see generation data, available solar resource and any errors reported by the solar PV inverters or battery system.
Residential Solar Power Installations FAQ
What is an inverter and where should it be installed?
An inverter converts the DC electricity generated by your solar panels into 240V AC electricity suitable for use in your home.
Inverters are usually smaller than a standard briefcase, and are situated close to your electrical switchboard.
Where should the solar panels be installed?
Wherever you have maximum sunshine and minimal shade.
Normally the solar panels will be installed as discreetly as possible on your roof, but if you prefer they can also be erected free standing elsewhere on your property.
Maximum solar energy in non-tropical South Africa is obtained by having the solar panels face north, and tilted upwards at an angle of 30 degrees. In tropical regions, where the sun is sometimes to the north and sometimes to the south, panels receive the most sunlight throughout the year when they are lain nearly flat with a slightly northerly tilt.