## The Formula for Working Out if You Should Buy an Electric Car

I have created what I think is a formula for working out if it makes economic sense to buy an electric vehicle. You can find it below:

$r_E = \dfrac{k}{100p} \left( f_I e_I - f_E e_E - \tau - \beta \right)$

$r_E = return \; on \; EV \\ k= kilometres \; travelled \; per \; year\; (km) \\ p= EV \;premium \; (\) \\ f_I= ICE \;fuel \;cost \;(\ \;per \;L) \\ e_I = ICE \;fuel \;efficiency\; (L \;per\; 100km) \\ f_E = EV \;energy \;cost \;(\\; per\; KWh) \\ e_E = EV \;energy \;efficiency \;(KWh \;per \;100km) \\ \tau = EV \;tax \;(\ \;per \;100km) \\ \beta= \;battery \;depreciation \;(\ \;per \;100km)$

Explanation of the formula

The way to think about whether an EV is worth it or not is to consider the EV premium, which is the difference between the higher cost of the EV and the cheaper internal combustion engine (ICE) car. So for example, as of December 2023, the MG ZS EV costs $42,990 whereas the petrol version MG ZS is$21,990, so there is an EV premium of p = $21,000. When you pay for this EV premium, you are effectively putting this$21k into an investment that has a return ($r_E$) which needs to be compared to the return of other investments. For example, suppose you buy an EV and spend and extra $21k and from the fuel savings etc you make 3% per annum returns ($r_E = 0.03$). If you believe that an alternative investment such as DHHF or VDHG has an after-tax return of over 3% then you would be better off buying the petrol MG ZS and putting the EV premium of$21k into DHHF or VDHG.

Another key consideration is battery depreciation. The EV premium is mostly a battery premium. The investment you are making is mostly in the battery. This battery has a return that you get from having access to energy in the form of electricity. Energy in the form of electricity is much cheaper than from petroleum. However, the EV tax and battery depreciation needs to be considered as well.

Looking at the MG ZS vs the MG ZS EV, the fuel economy of the MG ZS is 7.1 L per 100km and the petrol price is assumed to be $1.75 per litre. This means that every 100km you drive you are spending$12.43 in petrol.

However, for the MG ZS EV, the energy efficiency is 17.1 KWh per 100km and the cost of electricity under the Powershop EV Plan is $0.18 per KWh, which means that every 100km you only pay$3.11 in electricity costs. However, add in the EV tax of $2.50 per 100km (only applies in Victoria, Australia) and battery depreciation of$4.29 per 100km assuming battery life of 350,000 km and battery replacement cost of $15,000 and the EV cost is$9.89 per 100km, which is still cheaper than the $12.43 per 100km from the petrol car. Because costs depend on the distance you drive, whether it makes sense economically to drive an EV strongly depends on how much you drive. The more you drive (especially over 25,000 km per year) the more it makes sense to get an EV whereas if you drive under 25,000 per year, it starts to make more sense to drive a petrol car. Something else to consider is that when you pay for petrol, you pay for it using after-tax money whereas if you put the EV premium into getting an electric car, the lower cost per 100km you get is tax free. You need to compare the return from paying the EV premium against the after-tax returns from an alternative investment e.g. the after-tax returns of DHHF or VDHG. If we assume that you drive 25,000 km per year then the MG ZS EV costs$2,473 per year whereas the MG ZS costs $3,106 per year. Given the EV premium of$21k this means the return on the EV premium $r_E = 0.0301 \; or \; 3.01 \%$ .

A major uncertainty is the battery depreciation as it is difficult to know the battery life and battery replacement cost. In fact, most of the costs of driving an electric car seems to come from battery depreciation alone.

I shared this formula on Reddit and received mixed reviews. Some people raised very good points that I have missed in the formula, but I think overall the formula above is useful to know whether it makes sense financially to purchase an EV or not. Below are some other considerations:

• EVs have lower servicing costs.
• EVs are heavier and so tire costs are higher.
• Charging from solar energy is ignored as this would add extra complication due to the capital costs of installing solar panels and/or home batteries. Charging using solar energy is not necessarily free as some claim as there is opportunity cost associated with locking capital up and not earning returns elsewhere such as DHHF or VDHG.
• The EV tax in Australia currently only applies to Victorians. Laws may change in the future amending the EV tax.
• A recent FBT exemption provides an incentive to get an EV using salary packaging.
• Battery depreciation is considered but the depreciation of the ICE vehicles is not considered because it is assumed that depreciation for the EV and ICE vehicles are the same except for the additional EV battery depreciation. The assumption here is that when you buy an EV, you are buying something similar to an ICE car with a battery, so basically it is assumed that EV = ICE + Battery. However, the EV may depreciate more or less than the ICE vehicle depending on e.g. if governments increase or decrease EV taxes or subsidies. Some suggest that EVs depreciate faster than ICE vehicles, but this may change e.g. if the government introduces an additional carbon tax that applies to petroleum. If government is very aggressive in providing tax benefits for EV use, there is a risk that an ICE vehicle could become a stranded asset.
• The formula above ignores power or acceleration differences between cars. The MG ZS EV is supposedly more powerful than the MG ZS. It is claimed that EVs are very quick to accelerate. However, this is ignored in the formula as we only want to focus on cost minimisation.
• The formula ignores the environmental benefits of owning an EV as well as national security considerations (e.g. energy supply and price not being at the mercy of Russian or Saudi leaders).
• Batteries stored at the bottom of an EV lower the centre of gravity thereby making them safer. Furthermore, because EVs are heavier, they fare better in vehicle collisions.

Other thoughts and considerations

The decision to get an EV or an ICE vehicle is very similar to whether you buy or rent a home. When you buy a home, you lock up a considerable amount of capital into the home. The benefit you get from living in your own home is that you don’t need to pay rent. If you buy your own home and then rent goes up significantly, you are better off. Similarly, when you buy an EV, you lock up capital because of the added cost of the batteries. However, the benefit you get from EV ownership is that you pay significantly lower energy costs. If you buy an EV and petrol prices go up, you are better off.

We also need to think about the future. Currently the break-even point is about 25,000 km. If you drive more than 25,000 km per year, it is highly likely you should buy an EV. However, if battery technology improves, petrol prices go up, and electricity prices go down, the break-even point will go down. There is also huge risk that an ICE vehicle you own may become a stranded asset if government policy aggressively addresses climate change. In my opinion, it is more likely that electricity prices will go down and petrol prices go up rather than the other way around. Electricity comes from multiple sources e.g. solar, wind, nuclear, and even gas, oil and coal. However, petrol only comes from oil. As such the supply of energy sources that can create electricity is much higher than the supply of energy sources than can create petrol, so higher supply should result in lower prices for electricity as an energy source.

Based on these considerations, in my view, even if you only drive 15,000 km to 20,000 km per year, if you’re in the market for a new car, it is better to buy an EV. It is better to drive an ICE vehicle if that is what you currently own and if you don’t drive too much (less than 25,000 km per year).

## Rentvesting with NAB Equity Builder

Rentvesting (a mix of renting and investing) involves renting a place to live while investing. When many people talk about rentvesting, they refer to renting and investing in property at the same time. However, another way to rentvest is to rent while investing in the stock market via ETFs.

When rentvesting into the stock market, it is better to leverage into the stock market i.e. borrow money to buy ETFs. An EY study into rentvesting into the stock market found that renting while leveraging into the ASX 200 index using a margin loan with 50% LVR was approximately equivalent to buying a place to live in. However, this study found that without leverage, it is better to buy a home. More leverage provides higher returns (and higher losses as well should the market go down).

Rather that using a margin loan, I recommend using NAB Equity Builder (NAB EB) instead because the interest rate on a NAB EB loan is much lower. As at the time of writing this, the NAB EB interest rate is 3.9 percent vs the CommSec margin loan interest rate of 5.5 percent. Many people criticise margin loans because of the dreaded “margin call” but if margin loan interest rates were equal to NAB EB interest rates, I would prefer a margin loan because it provides more flexibility on when to make repayments vs NAB EB which requires monthly repayments. A margin call is not as bad as many claim it is because it provides you with more flexibility on when you make repayments whereas regular monthly repayments do not provide as much flexibility because you are forced to pay monthly. However, this added flexibility has a cost i.e. a higher interest rate.

Another major disadvantage with NAB EB is that it is not an interest only loan and you are required to make principal repayments which are quite high considering the loan term is only 10 years. Property loans are typically for 30 years, which spreads out the principal repayments. Some property loans are also interest only. Margin loans provide the most flexibility by requiring no interest or principal repayments so long as the LVR is below a certain level. The consequence of these higher NAB EB principal payments is that the level of leverage achieved via NAB EB is lower compared to what could be achieved via a property loan or a margin loan.

An example

I have created a spreadsheet that details a typical example of someone who saves $130k deposit to buy a home and compared it to someone who instead puts that$130k into the VDHG ETF using NAB EB. After ten years, the person who uses that $130k deposit to buy a home has a net worth of$760k whereas the person who uses that $130k to leverage into VDHG has a net worth of$790k. What this shows is that by renting you are not throwing money down the drain. In fact, both option yield fairly similar net worth.

Let’s imagine you’re thinking of buying a $500k apartment, which means that you’d typically need a 20% deposit of$100k. Add in the stamp duty and it is about $130k deposit you would need in order to buy this property. The alternative option is to put this$130k into NAB EB as a 35% deposit and buy $371k worth of VDHG. You might be wondering why the deposit amount is 35% and why VDHG is purchased. Basically you cannot achieve as much leverage with NAB EB as you can buying a property. When you buy a property, you have lower interest rates (2.69% compared to 3.90%) and you can borrow for 30 years vs NAB EB which only allows you to borrow for 10 years. The 35% deposit for NAB EB results in lower leverage (65% LVR vs 80% LVR for the property owner) but has similar cashflow. In other words, the property owner is paying$32k per year made up of $26k in mortage repayments,$5k in maintenance and $500 in council rates whereas the person renting also pays$32k per year made up of $38k in monthly debt repayments,$15k rent, -$15k in VDHG dividends (after PAYG tax), and -$5k in interest deductions.

What these numbers show is that the NAB EB disadvantage of high principal repayment is offset by the advantages that rentvesting provides i.e. you recieve dividend income and the ability to deduct interest expenses. The dividend income of $15k is after PAYG tax, which is assumed to be 37%. This dividend income covers the rent. After ten years, the property owner sees his or her property worth$500k grow in price to about $1.06 million and has debt of$300k (calculated using a CBA mortgage calculator), which results in net worth of $760k. The renter sees his$371k of VDHG grow to $813k and has zero debt (as NAB EB loans are for 10 years). The renter has a higher net worth of$813k vs $760k for the property owner, but we need to consider the capital gains tax exemption that the property owner has, which means that the ETF owner pays$22k in CGT. The $22k in CGT takes into account the 50% CGT discount. The calculations also assume that the renter realises capital gains when he or she retires and therefore faces a lower marginal tax rate and draws down$40k per year in retirement. Because ETFs are more divisible than property, $40k per year can be sold, which reduces capital gains tax by spreading it across multiple years. After capital gains tax is considered, the renter has a net worth after 10 years of$790k vs the property owner’s $760k. It is important to note that although renting comes out on top by a small margin, this analysis does not include measures that government often implement to entice first home buyers into the market e.g. recently there was an announcement by the Victorian government to reduce stamp duty by 50% for a limited time. These various incentives are not included in the analysis because they differ from state to state and typically do not last long. If these government incentives are included, the advantage for renters is likely to narrow or even disappear, but the main point of this analysis is that renting is not “dead money” and that you are not considerably disadvantaged by renting. VDHG vs one property is not comparing apples to apples One criticism of this anaysis is that the renter invests in VDHG, which is a broad and diversified high growth ETF provided by Vanguard that invests mostly in global equities whereas the property buyer buys one house. The property is not diversified and the price is estimated based on the price history of one Melbourne property on the BrickX platform (BRW01) that provided the highest returns (7.8% per year). In my opinion, this is more realistic as the property owner is buying one house to live in, and so the price history of one house should be used to estimate future returns. However, comparing diversified stocks (VDHG) to undiversified property (BRW01) is arguably flawed. If we are to use undiversified property (BRW01) for our analysis, we have higher risk and therefore higher returns whereas the high diversification of VDHG reduces the risk and returns thereby putting the rentvester at a disadvantage. To compare apples to apples, we’d need to compare undiversified property (BRW01) to undiversified stocks, but then the question is which stock? If we choose Tesla stock then this returns 62% annualised. A renter who invests in Tesla stock undiversified would have achieved much higher returns compared to the home owner simply because his capital exposed to a very high growth asset. However, even though the renter is able to select good stocks, he or she may choose a bad stock that performs poorly. It makes sense then that we use VDHG, which diversifies across almost all stocks globally. However, we need to apply the same approach to property to compare apples to apples. If we remove the advantage of stock picking for the renter then we need to remove the advantage of property picking for the home owner. A home owner may pick a great property through research of public transport, schools, etc but the home owner may pick a bad property as well. In order to compare apples to apples, we need to diversify across all property across multiple countries. However, by doing this, the returns of property start to look very bad. PWL Capital has considered this issue and looked at global diversified property vs global diversified shares: “To estimate this cost, we need to determine expected returns for both real estate and stocks. A good place to start is the historical data. The Credit Suisse Global Investment Returns Yearbook 2018 offers us data going back to 1900. From 1900â€“2017 the global real return for real estate (net of inflation) was 1.3%, while stocks returned 5.2% after inflation. If we assume 1.7% inflation, then we would be thinking about a 3% nominal return for real estate, and a 6.9% nominal return for global stocks.” In other words, global property returns only 1.3% after inflation whereas global shares return 5.3% after inflation. This shows that the returns of property are very poor compared to shares. A property owner may argue that he is able to select good property in certain suburbs or cities, but the renter who invests in stocks could also make that argument that he is able to select stocks like Tesla, Amazon, or Afterpay. Arguably, if you pick stocks e.g. Tesla or Afterpay (or even crypto such as bitcoin or ether), you are speculating whereas if you buy a diversified index fund such as VDHG or DHHF then you are investing. However, the same logic applies to property. If you select specific properties, which you must if you are looking for a place to live in, then you are speculating and not investing. If you buy VDHG rather than select stocks, you reduce risk. You could have purchased APT but you also may have purchased a dud like Flight Centre (FLT). By investing in VDHG, you diversify and reduce risk. With the property you live in, there is no ability to mitigate risk. There is no VDHG equivalent for the property you live in because you are only buying one property in one location (unless you’re a billionaire who has multiple properties across multiple countries). As such, you don’t know if you will select a property in a suburb that does poorly due to e.g. zoning or if the property you buy may have existing cladding, termite or mould problems. Once we compare apples to apples and compare diversified property to diversified shares, the renter is much better off than the buyer. If you have higher income, consider more leverage with NAB EB NAB allows LVR on VDHG of 75%, so leveraging with 65% LVR is well below the 75% limit. However, if a renter has high income, he or she is able to increase LVR. The table below shows ETFs where approved LVR is 80% which is the highest level of leverage. The highest LVR of 80% is allowed on global ethical ETFs (ETHI and HETH) and “old-style” Australian LICs (AFI and ARG). NAB EB also allows 80% LVR on a bond ETF (RGB) which in my opinion seems pointless. The age pension One argument for owning a property you live in is that it is not considered as part of your assets in the asset test for eligibility for the Australian age pension. However, if you own a liquid asset like ETFs then it is easy to simply sell that and buy a property in your own age if it is advantageous to do so. However, capital in the property you live in has an opportunity cost that may be greater than the pension you receive. Imagine you have a$1 million house and you get $24k pension per year from the government (which is the age pension payment for a single person as of January 2021). Now let’s imagine instead that you put that$1 million in a high dividend ETF such as IHD and get $60k per year (IHD has a dividend yield as of January 2021 of about 6%). You’d pay income tax on this but that is offset with franking credits. You’d be able to rent that house for about$30k (rental yield is about 3% in Melbourne) and have 30k per year in spending money.

I don’t recommend tracking your expenses or tracking your net worth because it is time consuming and because the information you get out of it is not valuable. If you track expenses, you can see where all your spending goes, but what matters is not what you spend your money on but how much you spend. If you spend such that your expenses are equal to dividend income, this ensures you don’t spend too much, and one of the benefits of living off dividends is that dividends increase over time as you invest more and as companies become more profitable, so there is a gradual increase in standard of living, which I think helps overcome the feeling of deprivation many feel when they are frugal. If you only spend e.g. $10,000 per year for the rest of your life, you are stuck on that level and do not feel as if you are growing or making progress, but if you live off dividends and your dividends grow, you feel a sense of personal growth. As for tracking net worth, when you diversify across multiple areas (e.g. retirement accounts, managed funds, ETFs, cryptocurrency, etc) then it becomes a huge burden to log in to each of these accounts to check the balance. What matters to financial independence is not net worth per se but passive income. You live off passive income, not net worth, and if you live off passive income then you’ll be able to assess automatically whether you have enough based on whether you are satisfied or not with your standard of living. Because living off dividends is simple, there are only two things you need to consider: how to spend your dividends and what to invest your work salary in. Most people have no issue with figuring out how to spend their money (e.g. holidays, books, smartphones, and coffee). What to invest in is more complicated, and generally I recommend buying broad and diversified ETFs with a slightly heavier allocation towards high dividend paying ETFs (or LICs). However, more important than what you invest in, in my opinion, is the “buy and hold” mentality. You should buy with the intention of holding these investments for a long time, if not forever. I also do not bother with rebalancing. For example, in recent years the Australian stock market has underperformed whereas foreign stocks (particularly US stocks) have done very well. There are those who rebalance by selling off US stocks to buy Australia stocks to maintain a certain amount to certain countries. This is far more effort than necessary, adds administrative burden by triggering capital gains tax, and does not add much value because if you feel you have too little Australian stock, rather than sell US stock, you can simply buy more Australian stocks. For example, in recent years, as US equities has gone up, I have purchased more high-dividend paying Australian stocks and ETFs e.g. CBA and IHD. Age in VDCO For most people who ask, I recommend Vanguard’s diversified ETFs. You cannot beat the simplicity of these ETFs. Whatever your age is, hold that amount in VDCO and the rest you hold in VDHG. For example, if you’re 30 then hold 30% VDCO and 70% VDHG. These Vanguard diversified ETFs diversify across just about all asset classes (e.g. Australian shares, international shares, emerging markets, small caps, property, bonds, etc) so you don’t need to worry about mixing and matching. The reason why you hold your age in VDCO is to broadly follow the “age in bonds” rule, which is insurance against retiring just after a huge market crash. There are many people who are anti-bond and claim that they are a drag on performance, that stocks always go up on the long run, etc, but this is not true. In fact, this is dangerous advice. There is no guarantee that stocks go up in the long run as the value of stocks merely represent company profits and there is no guarantee that company profits will go up in the long run. Even if stocks do go up in the long run, there are huge market crash (e.g. 50% decline) that emerge, not just normal business cycles but debt supercycles that can take centuries to materialize. You do not want to be in the position of being in 100% equities and then losing 50% just before you retire as this can really set you back and impact on the quality of your retirement. Broadly following “age in bonds” (government bonds, specifically) is insurance against such a scenario. In fact, of all the rules of personal finance, “age in bonds” is, in my opinion, the most important. You can pretty much invest in any exotic high-risk asset class (e.g. emerging markets, tech stocks, robotics ETFs, cryptocurrency, etc) but if you own your age in government bonds, you are safe. When markets go up, it is very easy to rationalize why defensive asset classes are poor quality. It is when markets go up that people easily covert to the cult of equity, but when there is a market crash or when there is a prolonged economic depression that lasts many decades or centures, many will understand and appreciate the wisdom of “age in bonds.” The reality is that when markets are booming, it’s easy to convince yourself why 100% equities or high leverage is a good idea, and the opposite is true when there is a market crash. It goes back to Warren Buffet’s quote about being fearful when others are greedy but also thinking about Ray Dalio’s idea that you must stress test your ideas because you are never be too sure in yourselfÂ because it is easy to be moved by your emotions as well as other psychological biases. ## Vanguard Australia Diversified ETFs – The Only Investments You’ll Need? Vanguard has always had diversified managed fund. I remember using these many years ago, but I stopped adding money into these funds as I was distracted by other new investments. However, when I look back the performance of my investments, I am blown away by the returns from these Vanguard diversified managed funds, and they pay regular quarterly distributions into my bank account. Furthermore, at the end of the financial year, Vanguard provides a full tax summary that you can simply give to your accountant (I use H&R Block). For simplicity and effectiveness, investing in Vanguard and getting H&R Block to manage your taxes is, in my opinion, a foolproof strategy. One of the main issues with Vanguard’s diversified managed fund was that its fees were quite high. However, recently Vanguard has released their suite of four diversified ETFs: • Vanguard Conservative Index ETF (VDCO) • Vanguard Balanced Index ETF (VDBA) • Vanguard Growth Index ETF (VDGR) • Vanguard High Growth Index ETF (VDHG). Investors now only need to determine how much risk they are willing to tolerate and then allocate money appropriately, e.g. if you are willing to take on more risk then invest in VDHG whereas if you want to take less risk you pick VDCO. Everything else is handled by Vanguard, which makes investing simple and easy. These ETFs can be purchased off the ASX, which can be done with an online broker such as CommSec. I try to purchase ETFs in$25,000 increments on CommSec as the fee is \$30, which is the most bang for your buck.

Most financial advice follows the “age in bonds” principle whereby you own your age in government bonds, e.g. if you’re 30 then 30% of your wealth is in government bonds. Whether you strictly follow “age in bonds” or not, the main principle is that as you are nearing retirement you reduce risk in your portfolio. With Vanguard diversified ETFs, you can simply carry this out by buying VDHG when you’re young but as you get older you start to buy more VDCO to reduce risk. Although not exactly conforming to “age in bonds”, “age in VDCO” is a simple alternative rule-of-thumb. For example, if you’re 30, own 30% VDCO and 70% VDHG. As you buy, simply buy whichever ETF you’re underweight in.

I love to dabble in new exotic investments such as ROBO and cryptocurrencies, but I try to follow the core-satellite approach, which states that you limit exotic investments (the “satellite”) to a small portion of your portfolio (e.g. only 30%) while the bulk of your investments (the “core”) are in low-cost passive index funds. Vanguard’s diversified ETFs are perfect investments to take the role of “core” investments.

More information can be found at Vanguard Australia’s official website on its diversified ETFs.

https://www.vanguardinvestments.com.au/diversifiedETFs/

For those who prefer managed funds rather than ETFs, see below Vanguard Australia’s page on its diversified managed funds.

https://www.vanguardinvestments.com.au/diversified