New off-grid solar for Sydney's Sustainable House

Two weeks ago I replaced the failed solar and battery system at my house.

Afterwards - last week - a family of five moved in, and I moved out to a studio at Bondi Beach.

So far the new system is easily meeting the electrical needs of the new occupants.

 •  New off-grid solar system installed by MV Solar

New off-grid solar system installed by MV Solar

The new batteries and solar panel system were designed and installed by Michael Valantine whose company, MV Solar, has been one of the pioneers in Australian solar.

I agree with these words on the company’s website:

“We are a multi-award winning, Hunter Valley based business dedicated to providing quality solar solutions. MV Solar is 100% Australian owned and operated and pride ourselves on being LOCAL and RELIABLE.

Michael Valantine, proprietor of MV Solar is a solar specialist with over 20 years experience in the solar industry and more than 30 years in electrical, electronics and medical electronics industries.”

Michael has been teaching solar design and installation at TAFE for over 30 years.

 •  On the right: melted, failed connector prevented power going into the batteries

On the right: melted, failed connector prevented power going into the batteries

During the removal of the failed Alpha-ess batteries Michael discovered one of the two key connections in the battery cabinet had melted and was not producing any power.  He found this by removing the backing screen to the battery cabinet and looking in it.

By comparison, a month ago three technicians from Alpha-ess visited to see why the system was under-performing.

They put a usb and a computer lead into ports in the battery system to upgrade the software.

But. That's all.

They did not know how to remove the backing screen or how to inspect inside the hardware in the cabinet.  (Or, they didn't care to.) Instead, relying on their computers they said the system was ‘fine’ and left. 

For most of winter, and at the time of their visit, I had had my fridge turned off during the night and day. Ever since installation the system had only provided at most 46% of the promised amount of power.  The solar panels never made half the promised amount of power, and the batteries never held enough power to carry me through a few days of rain.

And this was why I had asked Alpha-ess to inspect their machine.

As I was considering re-connecting to the grid I also asked the Alpha-ess company to let me know if the battery system was certified for grid-connection.

But no one from the company could or would answer that request.

And there was no information about the system in the list of certified products on the Clean Energy Council website

Batteries and inverters must first be certified before anyone may connect to the grid.

Other installation and design faults were discovered by Michael and I’ll blog about them later.  They range from panels not connected at all since installation, to faulty panels, to cabling that was not UV resistant and had failed in the three years since its installation in 2015. 

Earlier blogs about the unprofessional design and installation of the failed solar panels and batteries begin here

So I’m seeking a refund of all the money I paid for the design and installation of the replaced inverter and batteries and will blog about that when there’s news. 

Michael’s company located some gel batteries that had been used for 12 months and were being replaced as part of installation of a more powerful system; Michael provided them to me at a reduced rate.

Why did I choose gel instead of lithium ion batteries? 

Because experienced off-grid solar designers say they have no call backs for them whilst they’re always getting call backs for lithium ion systems, particularly those installed by recently arrived solar businesses.

I’m very grateful for Michael’s generosity.

In particular, I appreciate his lengthy experience and how that’s enabled him to create a design which supports my goal to stop my air pollution by staying off-grid. (Well, now its the pollution otherwise caused by a family of five that’s stopped, not mine. In my Bondi studio I’ve returned to a polluting life as its no where near off-grid; more on that return to a polluting life in another blog.)

Without his company’s support my house would probably have had to be re-connected to the grid as that may have been the cheapest and simplest option.

  • Left: Neighbour's roof with new panels going on to it; Right: my roof and panels

• Left: Neighbour's roof with new panels going on to it; Right: my roof and panels

I’m also grateful to my neighbours who’ve ‘lent’ me one of their north-facing roofs to put solar panels on to help deliver extra energy to the replacement batteries; thank you, Gus and Louise.  A large Jacaranda tree shades some of my solar panels.

We’ve agreed that the panels may stay there so long as they cause no leaks, that they will be taken down in a couple of months if they sell and the purchasers do not wish the panels to remain on the roof. 

As it turned out, when installing the panels Michael’s team repaired and refixed the neighbour’s roof in several places where it was leaking and improved its stability with modern roofing screws in place of nails over 40 years old and which had mostly lost their hold-down grip.

  • Gel batteries on dining room floor with MV Solar workers lowering batteries to Michael in the cellar

• Gel batteries on dining room floor with MV Solar workers lowering batteries to Michael in the cellar

The 12 batteries went in the cellar, under the dining room floor.

 •  The batteries were stacked lying down, side by side on insulation put down on the concrete floor

The batteries were stacked lying down, side by side on insulation put down on the concrete floor

The new system has these components:

·      Re-wire and reconfigure existing solar panels

·      New control panel, cabling and electrical protection

·      New 6  x  270 watt multi-crystalline solar panels

·      2 regulators (60 Amp MPPT Morningstar)

·      Selectronic SPMC 241, 24v 3kW inverter SP Pro

·      Morningstar Tristar Digital Meter (TS-M-2)

·      Fronius Primo 3kW AC coupled inverter (Selectronic Certified)

·      12 x 2V Gel batteries 800AH Neuton Gel Flat Plate

·      Removal of 6 maximisers and Tigo management system from existing six panels

The cost and the future

This system would save people all of their electricity bill if it was around $2.5 to $3k a year.

Let the sun shine on, the rains and nights come - the little house that could now can and does just use the sun for electricity.

Very warming.