{"id":78121,"date":"2023-08-25T11:37:15","date_gmt":"2023-08-25T02:07:15","guid":{"rendered":"https:\/\/www.solarquotes.com.au\/blog\/?p=78121"},"modified":"2024-10-02T10:31:28","modified_gmt":"2024-10-02T01:01:28","slug":"copper-solar-hot-water","status":"publish","type":"post","link":"https:\/\/www.solarquotes.com.au\/blog\/copper-solar-hot-water\/","title":{"rendered":"Copper Hot Water Systems & Solar: A Timeless Combination"},"content":{"rendered":"
\"Hot

Finally, something that’s genuinely German in the solar industry… sheet copper is no longer made in Australia, sadly.<\/p><\/div>\n

If we’ve noticed anything of late in the SolarQuotes office, it’s that water heating isn’t just a mundane task; it’s a subject passionately debated and deeply entrenched. Who would have thought?<\/p>\n

With all the talk of woke water heaters and the virtue signalling of efficiency, it seems even the most mundane things can be polarised these days. So, it’s not without personal irony I have to mount the case for traditional conservative values\u2014namely, an old-fashioned hot water service made from solid copper.<\/p>\n

Durability: It’s The Last Word<\/h2>\n

Our first hot water service on the farm was installed before mains electricity arrived in 1959 and lasted well into the next century. It outlived the original purchaser. So when I want a hot water service that’s the best thing bar none, I invariably get an all-copper tank, usually custom built by Bill from Gramall,<\/a> who’s been making them since 1976.<\/a> He doesn’t have much of a web presence, but his number is 0412 168 184.<\/p>\n

A Short History Lesson<\/h2>\n

Even before there was plumbing, hot water was always tied to the stove in your house, and sometimes still is. However, the Australian climate made having a stove-hot kitchen miserable. Many used a donkey: a tank outside under which you set a fire, and they’re still used in some places<\/a>.<\/p>\n

Some had “chip heaters”<\/a> that burned kindling or pine cones; when instantaneous hot water<\/em> meant a bath 20 minutes after you lit the fire. And there were wood, coke and oil-fired kitchen stoves with plumbing for a water jacket. These would be connected to a tank outside the kitchen, or in the roof space.<\/p>\n

\"old

This heritage-listed house in Yeoval, NSW has an original hot water service. Round 44-gallon drum to provide modest pressure, sitting on top of an insulated tank plumbed through the back of the chimney into the kitchen stove.<\/p><\/div>\n

What Does It Have To Do With Solar Hot Water?<\/h2>\n

With a tank in the roof storing water you heated with the stove, it wasn’t too much of a leap to put some pipes outside the roof, under a piece of glass, and get the sun to heat the water instead, and so solar thermal hot water was born.<\/p>\n

\"Copper

Beasley are long gone, but so well regarded people still want them. Here we see the guts of a traditional flat plate solar thermal collector. 25mm manifolds with 13mm risers and sheet copper to absorb heat and transfer it to the risers. Bill from Gramall is making these as I write.<\/p><\/div>\n

Thermosiphon Circulation – Just Add Heat<\/h3>\n

The elegant simplicity of these flat plate systems, (and of the later Solahart close coupled<\/em> units that came from Western Australia) is that they require no pump<\/a>. Whether it’s a wood stove or a solar thermal collector, heat rises, and that’s what circulates the water in the tank.<\/p>\n

The major downfall of solar thermal hot water, if there is one, is also simple physics. When temperatures fall, freezing water can tear a collector apart. There are solutions, like jackets full of antifreeze, expansion valves and elements, but probably the most novel was an all-plastic hot water service, the (not quite) Genius from the sadly defunct Solco.\u00a0<\/a> Most failed under warranty, the rest will last forever.<\/p>\n

\"Old

This Solahart would date to around 1978-82, and it’s one of three I know of that vintage still on roofs in Adelaide.<\/p><\/div>\n

Aren’t We Using Heat Pumps Instead Of Burning Stumps?<\/h2>\n

Heat pumps<\/a> are incredibly good at making hot water from a few measly watts of electricity, but heat pumps are complex<\/a>. A standard heating element is still a perfectly clean way to make water hot if you have lots of surplus solar power<\/a>.<\/p>\n

Using a smaller-than-usual element in combination with a relay controlled by your solar inverter<\/a> (or an even more precise solar diverter<\/a> such as a Catchpower Greencatch) means you can still utilise sunshine very effectively, without the complexity of frost protection.<\/p>\n

\"evacuated

Despite planning to hook up a wood-fired stove, this array of 30 evacuated glass tubes proved so effective it wasn’t needed, plus there are no issues with frost – sometimes a problem in the Barossa Valley.<\/p><\/div>\n

What Do I Recommend For My Own Mum, Uncle, Best Mates?<\/h2>\n

There is no one-size-fits-all solution, but the house pictured above was designed with this hot water system from the outset. Sadly, not everyone’s house is suited, but we have reinstated tanks in the ceiling space in a couple of cases because modern solutions were proven wanting. For example, an instant gas unit isn’t compliant when installed next to a window or door.<\/p>\n

\"a

A thing of beauty, complete with attic lighting and step-up for easy service.<\/p><\/div>\n

Why I Love Copper-Bottomed Hot Water<\/h2>\n

In no particular order, I’d like to point out;<\/p>\n