As I have pointed out before, some of the worlds cheapest and greenest electrical networks are privately owned.
I don't doubt for a moment that private enterprise could do it.
As one example AGL ran the gas supply in Sydney for over 150 years without much drama. Costs were kept down and they built the entire thing from scratch as a for-profit company. Their prices weren't expensive.
Now there's competition for the supply of gas however. Long story short you won't see anyone offering it anywhere near as cheaply as AGL's monopoly did in the past. Faced with competition and the need to offer competitive pricing AGL itself now charges 89% more in real terms (inflation adjusted) for gas in Sydney than it did 30 years ago in 1987.
There's the "competition equals lower prices" myth blown to pieces right there and it's the same nationally for both gas and electricity so far as residential and small business consumers are concerned.
Prices up 20% for electricity in several states this year for households. Here in Tas there's no competition, no choice of supplier, so residential prices went up 2% and small business prices were cut in nominal terms.
Economists will fall of their seat reading that one but it makes perfectly good sense to those on the technical side of it all. If you're running one system where scale is key and with most costs incurred during construction rather than operation then splitting it up, having multiple operators of physical assets and even more wanting to put their name on your bill never was going to result in lower prices. There will be some benefits of competition yes but they're blown out of the water but the higher costs due to loss of scale.
Alinta, AGL and the SA Government are all building (or have just built in the case of government) new generation in SA but not one of those plants is optimally efficient either technically or economically. A smart person would get the engineers of all 3, plus those from every other company who owns or is planning to build significant power generation, in the same room and coming up with a proper plan that is efficient and cheap. Trouble is the ACCC would have the CEO's in prison if they did that.
There's an inherent conflict between the economic ideology of competition versus trying to get the best outcome technically (which also minimises costs). Hence why competition has not in practice delivered lower prices - it creates an incentive to be more efficient but imposes serious technical inefficiencies in the process of doing so. At best the various companies will find ways to offset part of the costs imposed but none of them have got back to neutral on that one.
A single private company without such restrictions could do it reliably and cheaply for sure as could a well run government utility. Ownership is not the problem - industry structure and the triumph of economic theory over sound engineering is the problem.
We had the third cheapest electricity in the OECD with the state run utilities and that came with first rate engineering by any definition. Countless achievements at the time which others globally sought to replicate. Canada and NZ with their large hydro resources were the only ones doing it cheaper than Australia although for the record if Tasmania had been a separate country then it would have been #1 on that list for low costs (and would also have been #1 on the list for highest per capita consumption globally and that's no coincidence - scale is critical to minimising cost)
55 years after it was built Catagunya is still among the highest pre-stressed dams in the world today. It was the highest when built, the whole thing is a very different design to most dams being anchored to the ground via internal cables and being very light weight in terms of materials, and has stood the test of time. 30 years later Hydro Tas did the impossible and put the spillway straight down the face of a new rockfill dam - something which gained international attention and a few awards at the time and which a few others have since copied. Hydro Tas still sells its engineering expertise on a consultancy basis both nationally and internationally today.
The SECV was pretty proud of the fact that Hazelwood churned out power from coal at a cost no higher than hydro which was until that time always the cheapest way. Tasmania would have preferred they hadn't managed to do it of course but it illustrates the point that cost was always a key focus. 20 years later and they had Loy Yang up and running with generators 150% larger than Hazelwood's and a design that was directly copied by others (a private utility in the US bought the plans and replicated the whole thing).
The rest of the developed world was trying to work out the quickest way to cut reliance on oil circa 1980. In due course it was realised internationally that SECWA had already done it whilst others were still coming to grips with the problem. Power stations that could not just burn coal, oil or gas in the same plant but switch between them whilst remaining fully operational and even burn multiple fuels in the same generating units all at once if they wanted to. More world class engineering and importantly it was done specifically as a means of minimising costs.
And so on. There wasn't a problem until politicians decided there was a need for "reform". Ideology took over and now we've got among the most expensive power on earth, expensive gas too, increasing reliance on diesel-fired plant and an aging fleet of thermal power stations (coal, gas) that would normally be found only in poorer countries who used to buy second hand equipment from Australia and elsewhere because they couldn't afford the latest things.
Ownership isn't the problem, public or private it can be done well. Just keep the ideologically driven politicians out of the way.