Grid Tied (Connected to the utility and purely exporting power back to grid. No Storage) solar kit, designed for smaller type requirements.
80 x Renesola 250wp Premium Grade Solar Module – See Spec Sheet
1 x SMA 20kW TL Grid Tied Inverter Three Phase – See Spec Sheet
6 x Combiner box – STech
1 x Set roof mounts – See Roof Mounts
1 x Set MC4 connectors
1 x 200m x 4mm Aluminum core, shielded cable
*Optional Component – Grid Limiter for prepaid meters
Calculating Power Output
Our basis for calculation a 5.5 hour day, meaning that the PV module will output 110kWh without loss factors, naturally in some areas output will be greater or lesser depending on solar insolation levels.
Location Dependence and Legality of Grid Tied Systems
Much has been said about legalities surrounding grid tie installations, thus you have heard it here first. All municipalities generally allow grid tied installations, some are further ahead with their programs than others, as an example you can install under the Embedded Generation license in Benoni or East London or Cape Town etc. Some municipalities have different means of licensing and all it takes is a quick call you your electrical department to establish how to go about it. Soon, every municipality in the country will have open, easily accessible EG licenses or variations thereof.
Should your electricity supply be Eskom, then at present (June 2015) you are pretty much toasted, Eskom does not allow micro grid connected export systems, they have of course stated that they are working on this, but no date has yet been set. From Eskoms point of view, they see themselves as a bulk energy buyer and do not have the infrastructure yet for managing export billing on a micro scale, thus in general they are only really interested in 1mW (1000 kw) and over projects, but even then they are in no way obligated to accept your proposals.
In many, many, many cases, people with older electricity meters (wheelie type etc) have installed grid export systems without storage, Eskom is of course aware of this, but I have yet to hear of a single case where action has been taken against the client. I believe that as soon as Eskom launches its own EG license system all existing systems will be granted a compliance window to bring their applications forward, but we will only really know when that happens.
The Importance of Meter Type
For a grid export system to function you need to have a willing partner in the meter, as previously stated, the old wheelie type are the best but a grid tie can actually work with most types of meters. Should you have a prepaid meter or a digital meter you can either apply a grid limiter/Solar Log for SMA or alternatively request your municipality for a connection alteration (not free) along with your EG application.
Grid ties are extremely viable, it can be empirically proven to be the cheapest form of energy generation and is without question cheaper than Eskom. In general you can pay off a grid export system in 3.5 years just applying the energy savings to the capital costs of the equipment.
Every component here is selected based first and foremost on quality, they are not German products (except for the mounts) but are in common use and occupy primary position of leading products in the South African market.