Large scale off grid EV charging

It often gets asked on social media forums and at electric vehicle displays why off grid EV charging is not being built. The answer is: it will be eventually, it’s not technology holding it up, nor lack of renewable energy available, it’s frequency although not in terms of electricity but in terms of traffic flow.

Many EV drivers are already charging at home from off grid electricity systems, this is cost effective because of two important points; firstly they’re sharing the power generation equipment with general household usage thus sharing the equipment cost; also they are only using around 20% of the vehicles battery per day, 50% at most, this means they can delay charging until excess electricity is available.

With home charging it really isn’t that difficult to install a suitable off grid electricity system without too much overbuild, for a commercial site on a country road it’s vastly different. The random nature of traffic flow makes sizing a suitable generation system without massively overbuilding very difficult. On an average day in 2022 a regional roadhouse may get 4 electric vehicles stop to charge, that is zero to one car some days and 10 cars on other days, add in long weekends and school holidays and the EV traffic flow could be far higher. It’s not too difficult to install enough chargers for the busiest day but having enough electricity production and storage to charge those EVs would require a generation and storage system that would spend the best part of a week completely under utilized, it’s near impossible to make a business case from that.

Here is a very rough example to show why: On the busiest day 16 EVs stop to charge over a 24 hour period, if each EV consumes an average of 45kWh including charging losses, to provide 720kWh would require a minimum of 180kw of solar panels with the smallest battery set up of approximately 600kWh, and there sits the first issue. Batteries are currently too expensive to be only partly used 5 or 6 days per week, solar is cheap but having such a large solar array that’s producing vast amounts of unused power for most of the week is a waste of resources.

Mundrabilla Roadhouse – Nullabor Plain

So this is what needs to happen over the next few years;

  • 1. Battery prices need to fall significantly: this is not as big an ask as it seems as off grid batteries don’t have to be Lithium based, off grid locations have no shortage of room, energy density is not important, the best battery is one that provides the best cost per kWh over its guaranteed lifetime in an often harsh environment.
  • 2. One electricity generation system for everything: a shared off grid system is better value for money, but not only a shared system but a smart system where power consumption is carefully managed during busy time periods, water desalination and hot water systems can operate at times of low demand.
  • 3. Charging cost: EV owners will openly say they have no problem paying 45 cents a kWh in country areas but make it 60 cents at peak times and 30 cents when excess power is available and charging habits will change, most Australian drivers are already accustomed to being fleeced by fuel companies on long weekends at least this way they have a chance at cheaper energy.
  • 4. More electric vehicles need to be purchased in Australia: the bigger the flow of traffic in country areas the better the business case for building off grid charging facilities.

What is the short term solution?

A hybrid system of renewables and Diesel: as much as I dislike Diesel being used in passenger cars and pretend 4 wheel drives that never leave the suburbs it still has its place in country areas for another decade. Having a Diesel back up that covers the very busy days but only produces 10-15% of the overall electricity is a far better solution than the one Australia currently has. Most off grid roadhouses are powered close to 100% by fossil fuel (some have a few dozen solar panels) fueling up 99% of the vehicles that stop in with fossil fuels, a step in the right direction is better than no step at all.

Avoid Extension Cords Where Possible

There are three reasons to use an extension cord:

1) to avoid driving across a manicured lawn or soft brick paving.

2) to avoid stretching out your charging cable and making it a tripping hazard.

3) the third reason is not so obvious until you arrive at a charging site, especially tourist parks and other accommodation, many 10 and 15amp single phase outlets are positioned in such a way that the gen 2 UMC plugs can’t fit in the outlet due to the pins being positioned at right angles to the cable, the first solution many drivers take is to add an extension cord with a standard inline plug, this solution often creates another problem.

The first option is to try and avoid using an extension cord, longer cords have a significant voltage drop when charging from single phase, on an overnight charge that could result in 15 to 20kms less range in the same charging time. This voltage drop also means unnecessary heat in the cable that could shorten it’s useful life. The other issue in using an extension cable is it’s highly likely to add another tripping hazard unless it’s used wisely. As much as possible avoid using a 25 metre cable to cover a less than 5 metre span.

So what is the best solution?

Plan A is to always get the car’s charge port as close to the charging outlet without causing damage or inconvenience to the property owners, also the less distance between the car and the outlet the less chance someone will walk through the gap and trip over the charging cord.

If parking close is not possible or the outlet needs an extension cord with an inline plug use the shortest extension cord possible, if it’s a 15amp outlet make sure you use a 15amp cord even if your only charging at 10amps or less, I carry a 10 metre 15amp extension cord that has always covered the task.

A few more tips:

If the outlet is accessible to the public make sure it can’t be accidentally knocked out by someone else using the same power board, especially with outlets that face downwards.

Keep the cord as flat and straight between the car and charging outlet but add a half coil at the base of each end, that way if someone catches the cord with their foot there’s a shock absorber at the car end but most importantly at the power point end.

If you’ve used the shortest cable possible and still have plenty of excess don’t leave in a pile on the floor, lay it out carefully along the edge of a wall or somewhere else where clumsy feet can’t get to it.

Happy motoring.

Tesla Perth moving to Osborne Park

Contracts have been signed for the Perth Tesla location in the old Renault/Peugeot Dealership on Main Street and Scarborough Beach Roads. Test Drives begin soon from that location, but the service centre may take a little longer to move over.

Australind/Treendale Chargefox Location

The new ultra-rapid charging location at Australind/Treeton is nearing completion.

This location will have a pair of 350kW Tritium chargers which will be some of the fastest in WA – Older Teslas are unlikely to see much value over the nearby Supercharger, but Model 3 owners will certainly see better rates here.

WA to get a Big Battery

Expected to be Australia’s second biggest battery, the proposed 100MW, 200MWh big battery will be bigger than 20 tennis courts, side-by-side, and have the capacity to power 160,000 homes for two hours, and to be housed at the decommissioned Kwinana Power Station.

WA’s energy sector is experiencing a rapid transformation, with a major uptake of largescale renewables and rooftop solar. One in three households have rooftop solar panels and this is expected to rise to 50 per cent of households by 2030.

Increased pressure on WA’s electricity system and inaction could result in significant blackouts in coming years.

The big battery will support integration of more renewable energy and improve grid security. It can be charged during the day, when the sun is shining and energy is plentiful, and discharge this energy when it is most needed during the afternoon and evening peak.

Batteries will help the wider electricity system and the market by ‘smoothing’ demand issues, such as low load, which is encountered when customer solar generation is high but power demand is low.

October 4th Casual Meetup – Rotary Como Car Show

Our October Casual Meetup will be at the annual Rotary Como Car Show at Wesley College, South Perth. We have a few owners showing their cars, including the Targa-conquering Model 3.

This year the show is on Sunday October 4th, from 10am, Public entry $10 adult, $8 conc., gold coin under 18 – all proceeds to Rotary and Wesley charities.

Feel free to pop past any time for a chat, and also to chat with the many interested members of the public that come along. It’d be great if you’re happy to stay for a bit, and give those owners bringing their cars a break to go get a coffee!

So, you want to drive to Esperance?

Now that the Lake Grace DC charger is installed and operational the Perth to Esperance drive has become so much easier. I’ve completed the 700km trip in a Model S three times since early 2017 using the slow but reliable 3 phase AC charging. Update: It is now possible to do this trip with DC charging the whole way.

To make the journey as trouble free and relaxing as possible read on:

  • Perth to Esperance is 700kms via Williams and Ravensthorpe, the Perth to Lake Grace leg is 326kms, Lake Grace to Esperance 374kms.
  • On average you will lose 20 minutes of daylight driving East towards Esperance but gain an average 20 minutes on the return journey West, driving at dusk between Ravensthorpe and Esperance is not recommended so please take the above into consideration.
  • The Albany highway section of 168kms between Perth and Williams can get fairly busy, driving below 100kmh is not recommended or you’ll be very unpopular with the business people who use this road on a daily basis.
  • The Williams to Lake Grace section is flat and fairly good for range, take note if you’re driving into an easterly and factor that into the remaining range.
  • The 186km section between Lake Grace and Ravensthorpe is generally a low traffic road that can be driven a bit slower if needed but is not necessary. Be warned that at certain times of the year grain trucks are using this road, give them every opportunity to do their job as quickly and safely as possible.
  • The 188km section between Ravensthorpe and Esperance is not too busy but the traffic moves fast, it’s also a deceptive road, long sections of very good surface with random spots in need of repair from water damage, take note of the shire warning signs, it could very save you from tyre and rim damage.
  • Don’ be rigid in your trip plan, allow extra time for unexpected delays.
  • Spare tyre and jack, CARRY THESE ITEMS, although you are very unlikely to get a flat tyre, not having a spare when you need one will make it a very expensive and time consuming trip, not the type of memories you want while on holiday. Roadside repair kits are a plan C and are no substitute for a spare tyre in regional WA. Contact the TOCWA secretary regarding a loan spare and advice (free to TOWCA members).

When leaving from Perth I highly recommend you depart as early as possible; firstly there’s less traffic to deal with on the outskirts of town; secondly you have time up your sleeve to stop and take some photos; thirdly and most importantly it’s nice to arrive at your final destination, get the car on charge and relax with a drink before sunset.

How early? That’s up to you but sunrise is a great time to be on the road. If you don’t mind getting some driving done before breakfast the Williams Woolshed is a great first stop for a quick coffee or breakfast, just be aware the charging is extremely fast using the Tesla Supercharger, so get your order in quickly.

Lake Grace is an important charging stop and it’s likely that will take 40 to 50 minutes, if you’re a first time visitor it’s easy to use up that time going for a short walk and having some lunch. The DC charger is currently set to stop charging at 95%, this isn’t really an issue as by that stage the charge rate has likely dropped to a level where the Lake Grace DC charger has no advantage over the slower DC charging in Ravensthorpe.

Pro tips

  • Do not bypass working chargers on this route, even if you think you can get to the next one easily. It will not save you time and could very well delay you for a lot longer than you think.
  • There’s a good chance the moment you arrive a local will walk over and start asking about the car, make sure you plug in and confirm your car is charging before having a long conversation. Once again “Always be charging”.
  • Another tip is to carry the Chargefox RFID card as internet connection is often an issue when using the app.

Ravensthorpe is a small but lovely town that is well worth the stop even if you don’t need to charge, there’s an IGA supermarket on the hillside with a Cafe that provides a nice view. The DC charger in Ravensthorpe is 21 kW. If the DC is in use you can also top up charge at Ravensthorpe’s Green Haven caravan park which has a Tesla destination charger that cost the owners more to install than they’ll ever get back from the 50 cents per kWh charging fee. Back in 2017 when no one in Ravensthorpe had any interest in EV charging Claire at the caravan park stepped up. Unfortunately the caravan park is no longer available for charging due to the entitlement of some EV drivers. They also have some reasonable priced chalets if driving Perth to Esperance in one day is hard yakka. Charge far more than needed at Ravensthorpe so when you get to Esperance you don’t arrive low on charge and then have to worry about plugging in straight away.

Ravensthorpe IGA is a great spot to grab a coffee and check out the view.

Edit: There are now WA EV Network fast DC chargers in Esperance.

Esperance is a great place to relax for a few days, there are two locations with Tesla destination chargers (Smith Street Holiday House and Comfort Inn Bay of Isles) plus the horizon power type 2 and RAC Esperance Holiday Park via the Chargefox app (BYO cable). If you are staying for two or more nights, a 10 amp trickle charge is all you need. There’s plenty to do within walking distance including the local museum which has much more to see than just the Skylab wreckage. If you have time to spare a 90km drive east to the Duke of Orleans Bay is worth the effort, as well as the beautiful white sand beaches there’s a gem of a pub in the village of Condingup that back in 2017 served a tasty lunch.

Duke of Orleans Bay.

For the return to Perth, if you want to be a bit more adventurous there are two options, via Jerramungup (Tesla HPWC) & Albany or North via Kalgoorlie. If you want alternate recommendations let me know.

Happy Travels, Rob

Williams Supercharger coming soon

In fantastic news for all Tesla owners, we are thrilled to confirm that a supercharger station is being installed in Williams early next year at the Williams Woolshed. It will be a great day when our Eaton Supercharger finally loses its coveted most isolated Supercharger in the world honor.

Why is Tesla battery day a huge deal? It may not be what you think.

If you’re a longer term Tesla follower cast your mind back to March 2016, Tesla were about to display the mass produced Model 3 for the first time and the small (by today’s standards) Tesla fan base were salivating at the thought of a reasonable cost electric vehicle with the style and potential performance of the Tesla Model S. Anyone who had been for a drive in a Tesla product were excited, Legacy auto were not, Tesla was just background noise while they continued building vehicles with 20th century technology. As far as Legacy auto was concerned Tesla was just a niche product purchased by fanatics, the customer base was small and would soon dry up. 48 hours after the Model 3 reveal Tesla had over 300,000 deposits for the model 3, a car many would not receive for over 3 years, that was the last time Legacy auto would underestimate Tesla.

Anything Tesla announce on battery day will gain the full attention of the worlds car makers and likely lead to massive investments in research and development in an attempt to keep up with Tesla, the winners out of this will be the worlds car buyers.

Tesla battery day could bring a battery with better energy density, a battery that will have a useful life of well over a million kilometres, possibly a battery that can be charged at a far faster rate than currently available. It could be none of the above and it still won’t matter, Tesla only need one breakthrough and in the eyes of the fence sitters waiting to buy an electric car a Tesla goes from almost as good as ICE to slightly better than an ICE in total cost of ownership, it doesn’t take much to tip the scales for good.

So what is the most likely announcement on battery day? Amongst many small advancements I think the important one will be faster battery production allowing more efficient use of the facilities and factory workers that will lead to lower costs per kWh of batteries. This reduction in cost may only be 15 to 20% but that’s enough to create the tipping point necessary to assign the internal combustion engine to history.

Solar versus Superannuation as an Investment

I was discussing solar with a friend recently, as usual it focused on: how low the cost is in 2020; how short the payback period is; how cheap it is per kWh of electricity produced. As an investment how does it stack up compared to superannuation we quizzed. On the way home I had a thought, if the power bill savings are invested wisely what’s the possible dividends?

I did my calculations based on the most common system now being purchased for homes in Western Australia, the 6.6kw of panels connected to a 5kw inverter, this allows the maximum solar production without losing the low but still available feed in tariff, I avoided including the old 48 cents feed in tariff (FIT) as within 18 months that will be obsolete. In late 2020 the WA FIT for new installations is changing to 3 cents before 3.00pm & 10 cents after 3.00pm, as most new installs will likely face north-west or west to take advantage of the late afternoon sun the new installations FIT will probably average 5 cents per kWh across a full year.

Although a complete 6.6kw solar panel installation in Western Australia can be purchased and installed for some hard to believe low prices I based the calculations on a price of $4000, that’s very close to the average for Western Australia in March 2020. it’s important to remember that’s a full payment on delivery cost, not solar via a finance package.

Firstly, unless you’ve recently given up smoking or gambling the $4000 is not spare cash, it has some investment value or has to be borrowed, so how much return could you expect from that $4000 if invested via the bank or via superannuation.

Interests rates are very low or non existent at the moment so that $4000 would do well to attract 3% interest, you may end up with $7230 after 20 years, good luck getting 3% in 2020. If you could manage to get the $4000 into your super that averages 8% pa over 20 years and suddenly the resulting $18,650 is looking fairly useful, even at 6% the figure is reasonable at $12,830.

As an alternative what if the $4000 is invested in a 6.6kw solar system and you reinvest the power bill savings over the 20 year expected lifespan of the solar system.

Every household uses electricity differently but those with plentiful solar generation and a seemingly poor West Australian feed in tariff soon learn to consume from the panels rather than the grid. Of course, unless the house has a battery, purchasing power from the grid at 28 cents per kWh is unavoidable at night so for this exercise I going to use these figures:

  • Average daily solar production 24kWh
  • Average daily consumption of 19kWh split into 11kWh from solar and 8kWh from the grid, leaving 13kWh being fed back into the grid, over 365 days this would result in average power bill reduction of $1361 based on above mentioned kWh purchase price and feed in tariff.

Now imagine after the 3 year pay back period that $1361 was invested every year for the next 17 years, what are the possible returns?

  • Superannuation at 6%: $40,000+
  • Superannuation at 8%: $49,600+

As you can see if you invest in solar initially then roll the savings into super the returns can be very handy, now consider the possibilities if you made far better use of the solar electricity being generated on the roof. With a 100% electric powered home including heating, cooking and a heat pump hot water system powered from daytime solar, as well as of course charging an EV, the savings from avoiding the purchase of gas could also be rolled into superannuation, the end result will be well worth the effort.

Thanks to Peter Petrovsky for your advice and input on this article.

Rob Dean