Electrification Case Study

Getting off gas and including an EV

EXECUTIVE SUMMARY

The following is a case study of the full electrification of a house in the eastern suburbs of?Melbourne conducted over three months in mid-2024. It describes an initially failed attempt to outsource the project to a ‘one stop shop’ provider, and the subsequent owner led project that accomplished the same outcome at 50% of the price. This enabled the owner to invest the savings in an EV, boosting the overall benefit of the project. By selecting a vehicle that offered vehicle to load (V2L) the need for a battery to cover periods of power outage was mitigated.

BACKGROUND

The block, utilities and house

The house is a weatherboard dwelling on the front half of a large sub-divided suburban block. It shares the property with a townhouse built in the backyard accessed via a shared driveway.??

Both houses were connected to gas and electricity. Gas piping into the properties was not shared. Electricity meters for both dwellings were installed in a common cubicle at the very front of the property, so the externally mounted fuse boards for each dwelling did not have electricity meters.?Both details become noteworthy later in the project.

The 3-bedroom house was built in 1960, with minimal roof and wall insulation, and failed sarking under wooden floors. Stumps had been replaced, however the original concrete tile roof had reached end of life and was failing. The switch board did not initially have capacity for the scope of the project.

THE PROJECT

The goal of the project was to achieve full electrification and disconnection from gas supply. Drivers were a combination of aging and failed appliances, and the increasing cost for supply of gas, used primarily in winter.

Project driver #1 – the roof (2012)

The main areas of the houses roof face northwest and southeast.?In many respects the replacement of the roofing was the first step in the project as the concrete tiles had become brittle and prone to cracking. The existing roof would not have been able to sustain the weight of panels or the process of installation.

Replacement concrete tiles of the same style and colour and new supporting battens were installed, maintaining a consistent look with the townhouse sharing the block. At the time the roof replacement cost $11,500.

Project driver #2 – aging and failed appliances (2024)

Whilst the house had basic renovations during subdivision in 2005-08, by 2024 many appliances were old and failing.

A small external 70L gas hot water unit was struggling to service the 2-person household and was 20+ years old. The gas hot plates and electric oven were working but starting to fail and 20+ years old. The 3-star gas central heating had failed multiple times and due to slope on the block and resulting compressed under-floor ducting into the northeast of the house, was unable to heat the master bedroom. Failure of the heating unit for a third time was a trigger to act quickly before the 2024 Melbourne winter.

Two existing split system heat pumps in the kitchen and work-from-home study were 10-14 years old, however working fine and with reasonable coefficients of performance (COPs) of about 2.5.

Project scope

The plan was to install solar panels, an induction cooktop, a new oven, a heat pump hot water service, and replacement heating with one or more split system heat pumps. Replacement of existing heat pumps was considered.

A battery option was not considered as the owner had read that the economics did not support it, and power outages in the area were infrequent and generally maintenance related.

PLAN ‘A’ - A ONE STOP SHOP SUPPLIER

The initial plan in early 2024 was to seek a single contractor that could manage the project end to end, covering product selection, supply and installations - i.e. a one stop shop. This was due to the owner holding a job that did not leave time or mental capacity for researching, planning and executing the project.

This started off well with a video meeting with a well-known company offering a total service package. The company was well known for projects of this type and recommended by green energy groups supporting electrification. The meeting included a set of back-and-forth questions to establish the scope and objectives of the project, with next steps to be quotes across two price points.

Whilst most of the scope was quickly agreed, a significant item of conversation was options for the gas heating replacement.?After considering a whole of house ducted heat pump system, this was put aside in favour of the much lower cost option of adding two more room heat pumps to the two existing units. This would achieve full house coverage in zones (1x master bedroom, 2x open plan living, 1x work-from-home study) avoiding heat loss from poor insulation in areas not being used.

Plan A - quote

Whist the owner felt they had explained the main objective was to have an externally managed project that achieved the conversion with a minimum of disruption at a reasonable price, the message seems to have been received that a ‘best-in-class’ system was wanted. This resulted in a premium quote for $41,000, well over the expected price of the project.?It is not clear if this was a miscommunication by the owner or driven by the supplier.?

The quote included 8.2kW DC solar for $23,000 before rebates, using REC panels with optimisers, and a 10kW AC SolarEdge inverter. The heat pump hot water service was a split unit by Reclaim. The two heat pumps were Panasonic, one 5kW (open plan living) and one 2.5kW (master bedroom) chosen partly because of their air filtration and good WIFI interfaces. The larger unit was floor mounted as it fit the space and was intended primarily for heating (Melbourne remember!). Though $1,000 more expensive, a floor mounted unit gives a better spread of heat (floor to ceiling) and runs quieter (as the fan does not need to force warm air to the ground). The ceiling mounted kitchen air-conditioner would be used for cooling as part of the shared open plan space.

The household items (oven and induction cooktop) were independently researched and found to have considerable mark-up over RRP assuming a reasonable installation cost. As this was easily researched it caused the owner to question the value of the other items quoted which would normally have been harder to compare.

In a follow up meeting with the supplier these areas were discussed, with the owner requesting a reduction in solar and install only for the cooking appliances, which the owner would provide. Despite a 20% reduction in panels (8.2kW to 6.6kW DC) and 50% reduction in AC inverter capacity (10kW to 5kW) the quote only reduced 17% from $23,000 to $19,000. The total revised quote was $30,000 after rebates, not including supply of the cook top or oven. (NB: The household qualified for Renewable energy certificates (STCs) and energy efficiency certificates (VEECs), but did not qualify for the Victorian Government additional VicSolar rebates.)

The owner felt the total cost was still high and with the complexity of now having to research and purchase appliances, the project was no longer a ‘one stop shop’, which had been the primary objective. The owner felt if they were going to do some of the project they may as well do all of it.

PLAN ‘B’ - MULTIPLE SUPPLIERS

The secondary plan was to find local suppliers, with preference for companies who might do multiple items. In summary this worked very well, though did involve additional project management and likely extended project duration.

Solar

As the most prevalent and established service, the idea was to start with Solar and ask installers if they would take other parts of the project. SolarQuotes.com.au was recommended to the owner and proved a quick, easy, and effective way to source multiple quotes, taking less than 15 minutes to submit. Options were provided immediately with descriptions of the associated companies, but as ‘blind’ offers with no company names. Details of typical offerings, example premium equipment, and indicative pricing enabled selection of three companies. Quotes from these companies started arriving the next day. No expert knowledge was needed and the whole process was user friendly end to end. Some details about industry accreditations were not clear on the differentiating value. All three companies offered human contact and proactive engagement.

• Company A offered 5 quotes, ranging from $7,000 to $17,000. Two panel choices (Trina, Sunpower) and three inverter choices (Goodwe, Fronius, Emphase) were offered, including micro inverters. Conversation was good.
• Company B offered 1 quote for $5,200 (Eging panels, Growatt inverter). The quote stressed that with all rebates, installation would be ‘almost free’. Conversation felt like operations were focused on volume of deals.
• Company C offered 1 quote for $5,400 (JA panels, Solis inverter). The quote was detailed and personalised. Conversation spent time understanding the owner’s desired for a stress-free process.

On the basis of comparable quotes in the $5k region, Company C was selected on better rapport.

Aircon

Having established the value of a 5+kW floor unit, and knowing these were less prevalent in the market, the owner used this as the mechanism to conduct research. Panasonic and Mitsubishi were short listed based on availability, value, WIFI options, and look. Prices being comparable, Mitsubishi (MFZKW60KIT 6.1kw) was ultimately selected as more local installers were able to source and quote on it. The matching 2.5kW (MSZ-AP25VGD-A1) was selected as both could then be controlled from a single smart phone app.

• Company A quoted $7,000. This included a no obligation in house consultation to assess room size, installation location, and other work details. This included removal of the gas heater enabling cost reduction from rebates.
• Company B quoted $7,200. Did not include onsite consultation. Removal of the gas heater was listed as an increase to the cost even factoring in rebates.

On the basis of better customer service and an actual rebate from gas removal, Company A was selected.

Switch board extension

As mentioned in the introduction the switchboard on the dwelling was a sub-board, as the meter board was a cubicle at the front of the block.? This provided a significant advantage as the more typical house switchboard includes the Distribution Company’s electricity meter and the meter mounting board takes up over half of the space in the switchboard.? In most cases this only leaves room for a 17 or 18 slot circuit breaker unit, and this can be a limiting factor when attempting a whole of house electrification.

Both air-conditioning companies flagged they would engage 3rd party electrical contractors as part of the install, and so these contractors were also asked to quote on the switch board extension. Company A’s quote of $440 was lower than Company B’s quote $650, and the electrician was happy to take a call to discuss the job. This helped in selecting Company A for the air-conditioning job. The electrician was also happy to attend the site twice, to install the sub-board early in the project to avoid running out of room if the sequence of activities was not as expected.

With plenty of available space in this sub-board a second 12 slot circuit breaker unit was added, resulting in a total of 24 available slots, more than adequate for the majority of house electrification projects. ?However the electricians did confirm that it was a common mistake for people not to complete the switchboard upgrade as one of the first steps in the electrification process.? Rearranging the whole switchboard layout at a later stage can come at a high cost.

Hot water system

The owner quickly settled on an Apricus 260L all-in-one heat pump. This was due to the company’s Australian roots, 20 year existence, unit capacity, and included WIFI. WIFI was quoted on other units at up to $500 extra. Research was conducted by opening all systems from SameDayHotWaterService.com.au and comparing features and warranties. Apricus website was then used to find local stockists and installers who were engaged to quote.

• Company A quoted $5,000. Getting a quote was hard work and it was flagged they would need to wait on stock.
• Company B quoted $6,000. Contact was much easier and they had units in stock. The were also able to include installation of the oven and cook top as part of the job for $1,300 which had proven hard to find a contractor for. This included removal of the old appliances.

On the basis of better customer service, stock, and the ability to solve the kitchen install, Company B was selected.

Cook top and oven

Choice.com.au was used to research and short list options. On the basis of good ratings, low cost, and word of mouth recommendations the Ikea SMAKLIG induction hob ($820) and KULINARISK forced air oven ($1,430) were selected. Considerations included the number of induction areas with boost, and the ability to bridge multiple induction areas for larger cooking appliances.?

Project management

The solar was installed first, using all remaining slots in the existing switch board. The switch board extension was then installed. The hot water and air conditioning ended up falling on the same day, in which the cook top and stove were installed as well. This ended up being a good thing as the electrician was able to determine the best placement in the switch board for both and support both activities.

Gas disconnection

Finally, the gas retailer was engaged to terminate supply, turning up about one week later with a backhoe and removed the gas meter, and associated underground piping.

TOTAL PROJECT COST AND OUTCOME

Self-managing the project led to a 44% reduction in cost, saving over $18,000.

The owner has been incredibly happy with the result, especially given the regular 2-5 degree nights and morning that Melbourne has enjoyed this winter. The owner is saving approx. $2,000 per annum on gas for an only modest increase in electricity bills and is gathering more data to finalise the payoff period for the project.

POST-PROJECT OPPORTUNITIES

Electric vehicle and battery

The owner elected to reinvest the savings by investing in an electric vehicle, ultimately selecting a BYD Dolphin Premium. This was selected on the basis of similarity to the Hyundai i30 it was replacing, the high performance (150kW) and long range battery (60kW, 450km), the affordable price ($47,000), and the capability of BYD vehicles to offer 2.4kW of vehicle to load (V2L) thanks to their lithium iron-phosphate (LFP) battery technology.

The owner has had two 6-8 hour power outages since, and has been able to run all essential appliances for two people working from home, in both cases drawing only 5-10% from the battery. As the owner has been able to purchase the vehicle through a novated lease, both the EV car and by proxy the battery are essentially tax free.

EV retail energy plans

Quotations of around $2,500 were received to install a 32 amp, 7kW EV charger, with the benefit being that these can be set up to only charge the EV using excess solar generation that would otherwise be exported to the grid for less than 4 cents/kWh.

However the owner has been able to take advantage of their electricity retailer’s special offer of 8c/kWh from midnight to 6am for EV owners, and does this using an existing standard 10 amp, 2.3kW power point that was already in the carport. At 15kW/100km EV usage, this is approx. $1.20 per 100km, compared to their i30 which was 6.5L/100km at approx. $15. This represents an 80%+ reduction in fuel cost (after accounting for charging losses).

Over each week, in that six hours per night, the standard power point provides up to 96 kWh, or over 600km driving range, of charging.? As this well exceeds the owner’s weekly driving, and a fast charger is only a few blocks away, at this stage a dedicated EV charger has not been purchased.? This saving of $2,500 will fully pay for around 190,000km of driving range charging if the Retailer maintains the 8 cents/kWh overnight rate.

Also it should be noted that another retailer in Victoria in mid 2024 offers free electricity from 11am to 2pm each day, so there are other EV charging options.

CONCLUSION

The owner has achieved a full house electrification at a price within their budget, and without having to compromise on the quality of products or services. This was achieved by self-managing the project, which did involve research, planning and execution they had been hoping to outsource. They were able to invest the savings into further green projects and saving further household costs. This highlights the feasibility of projects of this nature, and the opportunity to increase green outcomes by reducing the cost of ‘all in one’ providers to more reasonable levels. This would also likely accelerate adoption, for those like the owner here who did not want to manage it themselves.

SPECIAL THANKS

The owner would like the thank the not-for-profit Yarra Energy Foundation, and especially the Corporate Secretary who provided consultation throughout the project. Without this support the ‘Plan-B’ would likely not have gone ahead, which demonstrates the key role that community bodies can play in accelerating adoption of green energy solutions.