Mike’s musings: Does technology drive behaviour?

May 10th, 2016, Published in Articles: Energize

 

This month’s musing revolves around the question whether technology drives people’s behaviour or behaviour drives technology. The technology in question is solar photovoltaic (PV) systems, specifically rooftop PV systems. The reason for the question is the rapid development and movement of the sector from one extreme to the other and a spiral towards what is perhaps the final optimum solution.

Mike Rycroft

Mike Rycroft

Rooftop PV, which started out as a system for reducing a consumer’s demand from the grid, was the preserve of wealthier consumers. As prices came down, more rooftop PV went up and the net-metering phase was entered, where “prosumers” found they could turn the electric meter backwards when excess electricity was fed into the grid. When net-metering proved to be not such a good idea, especially for distributors, the focus moved to on-site storage, with the realisation that it might be better to store electricity for your own use than give it away to the grid.

This move was also influenced by load shedding and grid failures, and was followed by the appearance of “designer” home storage units. One of the most rapidly developing areas is behind-the-meter storage, with many “smart” storage units designed for residential applications appearing. You can even couple to cloud based weather systems to determine what to do with your stored energy. Although Tesla has removed one of their models from the market, there are several other companies offering designer smart storage units for behind the meter solar systems.

This move has been followed by the realisation that stored electricity is the property of the consumer, and can be traded “behind the meter” and, with a particular smart storage unit now on the market it is possible to trade stored electricity behind the meter and over the garden fence with your neighbours, without going via the grid. Combined with this is the appearance of community solar “gardens” and residential communal solar PV systems. The next step is likely to be community storage, as the consumer system can be connected directly via a DC link to the storage with its own metering. All this behind the meter and off-grid, without the need for licences or regulations except the normal wiring code (which covers DC).

The cycle of rooftop solar PV has moved consumers from being utility dependant to individual system owners and now to larger co-operative ventures in the form of community solar and storage. Community solar gardens are taking hold in the US, and communal solar rooftop systems on the roofs of high density housing (HDH) units as well as retail properties are appearing. Several units are already supplying solar power to HDH residents in Australia, while locally a retail centre has installed PV on the roof and is selling the electricity generated to its tenants.

This may require the formation of some form of co-operative agreement but is a concept which could be considered by South African residential estates, where the body corporate would control the system and provide community storage with individual metering, independent of the grid. In many South African sectional title duplex complexes the roofs and carparks are common property, which the body corporate could use for communal rooftop PV. One wonders how legislation would deal with this, because no power would be sold to the grid or wheeled through the grid but exchanged between members of the residents behind the estate’s meter for internal consumption, surely a legislative nightmare.

One wonders whether all these developments are based on pure economics or on the individual desire to be free from dependence on major utilities, and feed the pioneering spirit still alive in this country. Is it that trading with your neighbours gives one that independent earthy feeling, or is it perhaps driven by the need to be seen to be green or to use clean power?

At my home, I installed a very complicated solar water heating system with a control panel which allows all sorts of parameters to be set and adjusted. I will probably never recover the cost in spite of substantial savings, but it does give me a feeling of being in control, and that I am obtaining some of my energy use from the sun.

On the subject of solar, the question of net-metering still raises its head, with some people believing that they can make huge amounts of money out of it. At a recent conference the statement was made that if net-metering was allowed, the rooftop solar market would take off because it would become profitable to over-install solar and sell the excess to the power utility or distributor.

This relies on the distributor paying the same rate as is being charged, which experience shows is not the case, and forgets the fact that this electricity has to be resold to other consumers at a higher rate. I do not want to be forced to buy electricity from someone who is only interested in lining their pockets. Seeing as this was a group of lenders one could ask whether they would be prepared to offer loans at the same rate that they are borrowing it – probably not!

Will this be the end of the spiral or will we see even larger projects developing with whole suburbs or towns owning communal PV plant and trading with one another without going via the grid? Whatever happens with technology, it seems that behind the meter storage will become a feature of rooftop solar PV systems in future, and smart energy storage systems are appearing on the market like mushrooms. Maybe the obsession with net-metering may well fall away, especially if time-of-use tariffs for residential customers are introduced.

Send your comments to: energize@ee.co.za

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