Having organised a few solar installations in the last few weeks, including one on my sister's house which is going in as I write, it has become apparent to me – again – that network companies are frustrating installations and charging fees in an absolute racket for services they're not even providing.
The network companies involved in my own experience are Citipower, Jemena, United Energy and Ausnet.
These companies all buy similar equipment to each other and run their networks in a similar way. In addition it's quite easy for them to hire personnel that have trained and worked at one of the others and thereby learn best practices.
But when it comes to solar they seem to be each making it up as they go along. This acts to unnecessarily hinder customers and businesses installing solar panels without any benefit in terms of safety or cost.
I'm covering Victorian distributors (owners and operators of poles and wires) because I live here and they're the ones I have direct experience with. But the same things are occurring in other states and in many cases the issues are even worse.
It's probably fair to say that these companies are being reasonable at the moment, especially at the small household scale. They're allowing 10 kilowatts of solar PV on a single-phase connection. This avoids unnecessary upgrades to three-phase power for those customers who want a decent sized system, and 10kW isn't too bad for covering all the needs of a big household maximising self-consumption and leaving spare capacity for an upgrade to batteries later. It's even better than that, they obviously know a thing or two about electrical engineering as they allow oversizing, being not too concerned if you put 13kW or 15kW or any amount of panels on your 10kW inverter, as long as the inverter is compliant with the relevant Australian standard (AS4777) so that only 10kW of capacity interacts with the grid.
Citipower used to be the trailblazer - progressive and willing to help customers moving to solar. And for them it should be easy, operating a network with one of the densest customer bases. This makes integration easier because a large, diverse amount of customers on their transformers means lots of load to offset against the solar generation. Also, many customers are so densely packed without a large area of roof space per customer (high-rise apartments, etc) that it's difficult to get a high ratio of panels to load, so any customer nearby wanting a big system will have the excess power readily sucked up by neighbours avoiding excess voltage problems.
But ... Citipower has decided to arbitrarily limit customers to 5kW on single phase (now they'll cite Australian Standard 4777:2, but that's not even accepted as a standard today and it isn't a direction to the power companies but rather solar installers). This leaves customers wanting a decent sized system to pay ridiculous amounts, as much as $3500, to get their line replaced with three-phase power if they want a system up to 30kW pre-approved. Citipower needs to get reasonable and offer 10kW connections again. The current situation is disgraceful and we need some intervention from the new energy minister, Lily D'Ambrosio.
For the Powercor part of the business, it's reasonable to expect that there may be some difficulties in integrating solar in weaker parts of the network, as the network takes in all of western Victoria – which means long SWER (single wire earth return) lines out to rural farms where controlling voltage can be difficult. But for homes in townships there shouldn't be a problem integrating 10kW on single-phase connections. After all Jemena and United accommodate this and their network includes areas around the outer fringe of Melbourne with similar technical circumstances.
Ausnet is the worst power distribution business in terms of restricting solar. If you live east of the Hume Highway in Victoria and you want solar panels you're going to have to be prepared to jump through hoops or learn to accept a 3kW or 4.5kW connection.
Even worse, they don't seem to understand basic electrical engineering. They ban oversizing of inverters for some unfathomable reason, so you can only have 4.5kW of panels on your 4.5kW inverter. This means customers are left to put additional panels on their roof and connect them by oversizing their ~4.5kW inverter without notifying Ausnet. This situation is far less than ideal.
Sure Ausnet's has a number of SWER lines that have legitimate technical constraints that might necessitate restrictions on the size of solar connections (although they shouldn't escape some scrutiny here). But they need to pull their socks up and offer 10kW connections in their densely populated areas right through to towns the size of Maffra and Orbost, just like Jemena and United do.
It's high time Energy Ministers moved to end restrictive connection rules that lack any sound technical basis in terms of power quality or safety. These are anti-competitive, working to restrict customer choice that could cut their own carbon and energy footprint while also pushing down wholesale power prices for others as well.