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When it comes to electrification, don’t put the car before the house.

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Before I start, I am going to say something that readers of my blog will probably already come to understand. I do indeed like electric vehicles. I want them to succeed, and more importantly, I like the technology, the power and the performance they have. What I don’t like is this argument that electric vehicles are this silver bullet that we have to fight climate change, and this way of consuming our way out of the problem.

Truth be told, I love the idea that you can just plug in your car and leave home with a full battery every single day. However one question you might be thinking to yourself as a homeowner, is whether or not it is better to buy a solar panel and battery storage solution, or buy an electric vehicle in order to reduce your climate and financial impact. Green energy after all, is cheaper than gas and coal, and cleaner at the same time, even if you factor in its mining and extraction, in the same way that electric cars (after 3-5 years of ownership) are cleaner than their ICE counterparts.

The thing is, electric cars in particular have a huge issue. They’re horrendously material inefficient.

So, I am going to advise you, when it comes to electrification don’t put the cart before the horse, or rather, don’t put the car before the house. Here’s why.

1: Cars rarely appreciate. Houses rarely depreciate.

If you’re like me and you keep your ears to the ground, you’re probably heard about the recent EV price crash. With companies like Hertz and Sixt dropping EVs from their fleets due to high repair costs, and insurance companies in some cases charging double the price of an EV compared to its ICE counterpart, people are second-guessing whether or not EVs make financial sense. On top of this, with new battery technologies coming out every five years or so as of recent, with LFP packs suddenly becoming the new hotness when it comes to battery tech due to its better safety and lower dependence on rare earths, it’s no surprise that the average price of an EV has taken a massive hit when it comes to depreciation.

Looking at Carsales, which is in my opinion one of the more reliable websites when it comes to looking up Australian car prices, you can find 2021 Tesla Model 3 Standard Range models starting at around $50,000 in Western Australia. This is a three year old car and these cars average around 20,000 to 30,000km in terms of mileage. Consider that when new, the Model 3 standard range was $68,000. That’s $18,000 in depreciation in three years, putting them in the same league as high-end luxury cars in terms of percentage depreciation.

Now, granted, all cars depreciate, some more than others. In my previous blog post, I mentioned that I was looking at a brand new ND3 Mazda MX5. Now, ND2 MX5s in the same grade in the same model year of that Tesla (2021), with roughly the same mileage retail for about $40,000. Brand new, they could be had for about $47,000. That’s only $7,000 in depreciation over the course of 3 years; a way, way lower rate of depreciation than the Tesla.

Now look at say, what my brother-in-law recently purchased; a standard model 80 Series Toyota Landcruiser. If sold in today’s money, that Landcruiser would be say, about $76,000. But consider that in 1990, it sold for around $36,000. He recently purchased it for around $30,000. This means that in 34 years, that Landcruiser has only depreciated around $6,000 over the course of its life. Granted, this cruiser’s in superb condition for its age.

So why do some cars depreciate faster and others don’t? Well, it’s entirely because of three factors. Rarity, desirability and reliability. NA MX5s are so expensive these days, because very few pristine examples exist, which makes them rare. NA MX5s are desirable because they are simple, lightweight and balanced sportscars with excellent aftermarket support and a cult fanbase to back it up. Finally, NA MX5s are mechanically simple and very cheap to fix, with an engine that is proven, tested and reliable.

Now take for example, the current car I drive. A 2010 Hyundai Getz. It’s not exactly rare, however it is desirable and reliable. This basically means that they are now relatively expensive for what you actually get when compared to a new car. Consider that a 2010 Hyundai Getz can sell for anywhere between $3,000 (>200,000km) and $10,000 (<60,000km) for a good example. The model in particular we have, a 1.6L SX Grade, was sold, brand new in 2010 for $13,990. We bought the car for $6,000 with 96,000km on the clock. If we sold it today with 110,000km on the clock, with the modernising upgrades we’ve done to the car, we’d probably get $8,000 for it because of the increased desirability for mechanically simple small cars, meaning by owning this tiny little silver nugget, we’d actually make a profit.

What’s the take-home from all this? Well, cars rarely appreciate, and homes, rarely depreciate. This is because land in locations that are desirable is rare, it’s of course, desirable, and having a good location means people want to build businesses and schools in that location, making the desirability and rarity even higher.

Now this is by no means advocacy of using housing as an investment instrument, nothing of the sort, in fact. It’s not the house that appreciates in value, as it is very much a consumer good, and desire for consumer goods, as well as the wear and tear on those goods, affects the prices when in secondary markets. the land is what makes things desirable. Its location, its proximity to services like schools, shops, services and transit links, the surrounding neighbourhood and its crime rate, all sorts of stuff goes into how much your home’s worth.

One thing that’s factored in is the amenities your home has. Now, as of the time of writing, my home has appreciated about $100,000 in value, no thanks in part to inflation and the housing crisis. I do not factor this into the reasons why I bought a home in the first place, this is just the simple facts of the market economy. The other thing that hasn’t been factored in is the upgrades that’ve been done to the place. The security system, the multi-zone air conditioning, and of course, as the title of the article talks about, the solar.

Now, when it comes to Solar I didn’t half-arse it. I went with Enphase, the best solar system money can buy in my opinion. Now many people will tell me I paid too much. Those people will likely be complaining when they have a dead panel in their array that solar’s a scam. The truth is, you bought the wrong system. Likewise for those who choose cheaper appliances or cheaper air conditioners or hell, cheaper cars from cheaper brands like MG or BYD. There’s a mantra you’ve probably heard before. Buy once, Buy right.

The brilliant thing about the Enphase system is the fact that each panel has its own tiny little inverter on the back side of the panel. In the event of a panel failure or inverter failure, the app tells me the issue and lets me know that it needs replacing, however the brilliant thing is, the panel array will still keep generating. I went with this system because of the simple fact that because I live in an upper floor apartment, it’s going to be quite tricky to access the panels in the event I need to say, replace a dead panel. It also means I can save up the money to pay for any dead or broken panels or inverters and still have the panels generate somewhat sufficient power.

What’s also brilliant is that they also provide a really nice battery backup solution in the form of a modular and expandable battery storage system that can be grown in 5kWh modules. That way you can monitor your home’s consumption and spec out your battery storage based upon how much you actually draw from the grid overnight when the sun’s not there. For my home’s case we’ll likely need 10-15kWh of battery storage to sufficiently cover the cooling costs of our home in summer. It’ll also add value to the home, and, as you’ll see in my next point, it’ll end up being significantly cheaper overall because…

2: Solar arrays are cheaper than EVs.

The price, fully installed of a 15kWh Enphase Battery array and a 6.9kW/4.9kW (Panel/Inverter output) Solar system from a licensed Enphase installer will set me back around $32,000. Currently, the most efficient EV on the market is a Tesla Model 3 Standard Range, which costs $68,000. The Tesla, is a rapidly depreciating asset, whereas a house holds its value way, way better.

So why is this the case? Simple. Houses use less power than EVs.

A Tesla Model 3 is a 1.6 ton car, running on rubber tires, that contact with a really rough surface, that has to haul both itself, up to four humans and a bunch of cargo around. Using 1.6 tons of steel, batteries and other materials to haul what amounts to four fleshbags is horrendously inefficient in terms of transit. Consider this for a second. A Transperth B series train has a 1.44MW power output into its traction motors, of which there are eight of them. It can also carry, in a standard 3 car set, 240 seated passengers, and 320 standing passengers, for a total of 560 passengers overall when fully loaded. Meanwhile, the Tesla Model 3 has a 194kW motor powering the rear wheels.

Now assuming the power output is maxed out on the Transperth train at all times (which it isn’t), but let’s assume the train driver’s done a line of coke and has decided to max tilt the train. Well, that means only 2kW of power is being used, per passenger, at full load to accelerate the train. This is less than the max burst power draw of an average Australian 240v socket. Meanwhile, if you as the Tesla driver, floor the throttle to accelerate you to top speed, you’re using all 194kW to get yourself to top speed. If you say, accelerated 560 Tesla Model 3s up to full speed at the same time, the combined power draw of those cars is 108 Megawatts.

That makes this fleet of Tesla cars almost 100x less efficient than the train.

Now you’re starting to see why Elon has such a rageboner for public transit, right? On pure power efficiency alone, trains absolutely destroy cars. But you want to know what else destroys EVs for power efficiency? Houses.

Your average home consumes, at most, about 20kWh of power in a day. The maximum power draw allowed for an average home, is 80A. A simple bit of napkin math and calculating for some efficiency discrepancies means that if you loaded up your master circuit breaker to maximum capacity, you’d be drawing at most, 19.2kW, although you’re more likely to be drawing at most, about 5kW at a time.

The brilliant thing about the Enphase App is you actually get to see how much power you consume and when it’s consumed. In my case, during summer I drew an average of 0.7kW of power overnight, from running a single 2kW Mitsubishi Heavy Industries AC in our room to keep it cool (on Eco mode, of course)

This pretty much means, if I assume that I get a solid 8hrs of sleep, i’m consuming 5.6kWh overnight to cool our bedroom. Consider too that I’m also cranking my oven at night to cook dinner, using lights and computers and so on, you could assume then that the maximum i’d consume during summer or winter is roughly 15kWh of energy. Consider that to generate power in Australia, on average each kWh of energy from non-renewable sources outputs about 550gms of CO2. Well, if we do the math again, that’s 3 tons of CO2 just to run my appliances at night. Consider that it takes about 16 tons to make a 72kWh Model 3 Long Range battery.

15kWh of batteries from Enphase, coupled with an IQ Controller 3, sets you back around $23,000, about the same as a brand new Kia Picanto GT with some spiffy wheels, or an entry level Toyota Corolla. The cost of this whole setup to produce as far as CO2 is concerned is around 3 tons of CO2 equivalent (based on a conversion rate of 76.6kg of CO2 per kWH of produced LFP batteries, plus adding some additional costs for the production of the electronics to drive these batteries.)

Based on the carbon reduction impact, the batteries would pay themselves off in a single year in terms of CO2 emissions.

In terms of saved power bills, assuming that all we’d be doing is paying the $1/day supply charge from Synergy over a 60 day cycle, average power bills would’ve dropped from $150/2mo to $60/2mo. Now sure, that’s a 42 year payback scheme, but if you factor in the profit made from output power during summer, the payback rate is about 15-20 years. Assuming you discharge the pack from 100% to zero % every night (which you won’t), those packs will last about that length of time, and offset the entire carbon emissions of your house in the meantime.

Think of it as a way to pay for 25 years of power whilst only emitting 3 tons of CO2 in the process of the battery install, and about 6 for the solar panels. You’re offsetting 25 years of CO2 for the cost of 2 years worth of CO2 and doing so whilst adding value to your home.

For the same power consumption used to charge 100 Tesla Model 3s from 0-100%, you can power 290 houses for an entire day. That is an power efficiency gain of 200% over the Teslas. Considering that we’re making a 200% daily efficiency gain with every house we put solar panels on, it makes perfect environmental and financial sense to put batteries and solar onto your home. For half the cost, you get double the impact. And that’s because…

3: Houses don’t really move.

I mean, unless you’re in one of them fancy pants moving houses that’re all the rage… Wait, those are called Motorhomes? Never mind. Well, we all know the old joke about houses and elephants, right? They certainly can’t jump, and houses certainly can’t move. As such there’s no way you’re going to efficiently move a 100 ton house. (fun fact, that’s the average weight of an American house. Amazing what you learn in a fervent googling session)

So anyways, the simple fact that the only real law of physics a house has to deal with is the fundamental law of thermodynamics (ie, heating and cooling), it really doesn’t have to waste a whole lot of energy on any of that Newtonian nonsense. (I mean it still does, but not with itself, just with the vibrating molecules of the air inside the walls)

Teslas and other EVs have to move themselves, stop themselves, play fart noises through the speakers, heat their cabins, heat their batteries, (or cool them, I don’t judge), and do so whilst doing all that in an environment that is outside of the ideal for both itself and the cars occupants.

Roads are hot and cause a lot of friction. This is why you hear people harping on about how electric cars chew through their tires like they’re kids chomping through bowls of that silly rabbit’s sugary rainbow cereal. Tesla makes really efficient EVs mostly because they make relatively light EVs. A Model 3 Standard range weighs just 1600kg and has a 58kWh battery. Currently the lightest EVs on sale right now is the Kona EV from Hyundai, but that’s still a whopping 1575kg. Even the tiny little BYD Dolphin, which you think would be like, super lightweight, weighs more than a Tesla Model 3 does, and the BYD Seagull, their supposed microcar? That weighs 1200kg!

The truth is, EVs are heavy. Houses are also heavy, but houses don’t move. They’re not subject to friction, air resistance, rolling resistance, mechanical losses, all the things that put all that load onto a vehicle are almost non-existent. Okay, unless they’re tower blocks, but then again. You can’t go zoom in a tower block. Unless you’re in Singapore having an electric scooter race on the roof of the Pinnacle@Duxton’s skygarden.

In order for EVs to be viable as alternatives to ICE cars, they need to be as light as their ICE equivalents. the BYD Seagull aims squarely at the Kia Picanto GT, a car that is 200kg lighter than it. The BYD Dolphin? That’s taking on the Toyota Yaris, a car that weighs 1025kg, almost 600kg heavier. the Tesla Model 3? That’s taking aim at the BMW 3 Series, a car that’s 200kg lighter.

When Mazda designed the MX-30, they offered a model that was fully electric, but made it weigh as much as its REV and Hybrid counterpart, around 1750kg. To make that car a full EV, they could only offer it with a 200km driving range from its frankly, small (for a car at least) 30kWh battery pack. With the range extender, it could only pack in a 100km range before the range extender kicked in, but the battery needed was way, way smaller, and it offered a total of a 650km range per tank. The standard Hybrid version? 797km to a full tank. This is from a not particularly aerodynamic vehicle mind you, the MX30 is a big chonky SUV looking thing, but it goes to show that ICEs can get much bigger ranges. The best part? The Hybrid gets more range because it’s almost 100kg lighter than the REV, and it has a bigger, more powerful engine, so it’s faster than both of them.

It showed to us that even in the most ideal scenario, in the same body type, EVs in their current day absolutely do not cut the mustard as true ICE car replacements without making some significant sacrifices in weight and significantly wasteful gains in material consumption. PHEVs are doing quite well, but even then, they only eschew their emissions so long as people remember to plug them in at night. Hybrids are fuss free, but also electrically and mechanically complicated, but also, proven, which is why Toyota puts hybrid systems in their Camry and Corolla, and why the only PHEVs they offer are the Prius and Rav4 Prime, which they also offer in standard Hybrid form for old time’s sake.

For the same 58kWh of LFP batteries you find in a Tesla Model 3 Standard Range, you can sequester 4 houses worth of CO2 over 10-15 years assuming you go with a 15kWh battery system from Enphase. For the price of a Tesla Model 3, you can do this for three houses over that same time period. You can still keep your ICE car and cut your per-person emissions in half whilst not losing a single dollar (due to inflation and appreciating housing value) over the course of the lifespan of that car. In that same time period, if we assume the lifespan of a Tesla Model 3 battery pack is 10 years, just like the house, you are using four times the resources for twice the price, at a climate reduction rate that is half that of just putting batteries on your house in the damn first place.

This is because as I said, houses don’t move. You can use a smaller battery, use less resources and spread them out over more houses. Batteries on houses are also drawn at a much, much slower rate, meaning less fire risk, less thermal damage risk and most of all, less wear and tear on the battery.

The thing is, us aussies have been doing off grid battery storage for years. If you’ve ever been out bush to an old cattle station, you’ll know of the battery room, a room stacked to the roof with old lead-acid batteries, connected to a house-scale 240V inverter, connected to a bunch of solar panels, with a diesel generator backup. We’ve been doing it since the early 80s as a way to get electricity out bush to where the poles and wires don’t go. It’s certainly nothing new.

So what about if you put the two together?

You’re rich. You’re also doing the world a solid, but don’t expect the CO2 emissions from an EV vs an ICE to pay themselves off in such a quick timespan. Solar and Batteries pay themselves off, when installed together in 3 years vs 5 years for the average EV, and if you’ve already got Solar, the CO2 cost of batteries pay themselves off in a year. So that’s 7 years of sequestering you’ve gotta do. Oh wait, your car’s going to be dead in 10, which really means you only get like, 3 years of truly zero carbon living. There’s also the need for gridscale solar batteries to offset apartments and industrial capacity, the need to build rail lines and e-Buses and cycleways and implement mixed use development and it goes on and on and on and why the hell is this sentence so long…

Well it’s because we don’t have a long time to do what we can. People are also getting hostile towards EVs, for very, very good reasons. They consume a lot of resources, they’re more efficient as they get smaller (See my previous post about E-motorcycles and eBikes and how they’re absolute carbon reduction gigachads), and automakers really, really do not want to sell you a car that’s lightweight anymore. They want you to get into a more profitable and bigger car. They want you in cars that are less reliable, which EVs, certainly are not reliable. Look at the Cybertruck and the ADAS issues on the BYD products as prime examples.

I mentioned previously that EVs are for the rich. If you’re throwing down on finance, solar panels and batteries are going to cost you way less than a car. Houses appreciate and cars depreciate. Houses don’t move. A top-trim Solar and Battery system from Enphase is half the cost of even the most efficient EV and offers a much greater per-dollar CO2 reduction impact than an EV.

So when it comes to electrification, it makes sense to not put the car before the house. Go Solar, Go batteries, enjoy your Petrol car until it’s time to make the move. When Toyota and Mazda make the Corolla and MX5 Electric? It’s time to move. Until then, motor on.

Beano out.