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Discussion Starter · #1 ·
So excusing where I have uploaded these, I have just shoved them in the Google Drive for my Business, not affiliated to my EV endeavours in any way, was just convenient.

I have created a spreadsheet for doing your EV Conversion, and it will tell you exactly how much it costs, and a way to calculate the break even point, and the practicality of your conversion.

So for example, I am using a donor Nissan eNV200 (Leaf) for my conversion, all values are in my local currency (AUD), however I have intentionally left out a currency symbol for ease of transfer, you can change the value to currency for your local currency if you so wish using the standard spreadsheet formatting tools.

ANY BOXES THAT I HAVE LEFT GREY, LEAVE THEM ALONE. THEY ARE FORMULA BOXES.

Anyway, here's some examples:
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So you can see here that I have a 24kWh battery, and LeafSpy is giving it ~80% SoH, however I'm told that as it's been sitting ~30% for so long, that it's likely to be a bit off in it's calculation. So I should drain it as close to 0% and give it a full balancing recharge and I may get some SoH back. It's only done 11,000kms and that's a big hit to the SoH from that short a distance.

I'm also assuming the conversion will be ~20% LESS efficient once I shove it in the new car, so I have stuck 20% in that box, if I was going from say a Tesla to a VW Beetle, you may get more efficiency out of the motor, so you would stick a negative value in that box, like so:

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As you can see the final box, calculated new range jumps back up as the motor is more efficient in the conversion than it was in it's original car

Moving along, we can start to crunch some numbers on daily usage, so for example a 20-80% usage of the battery, a 10-90% usage, or a 0-100% usage can all be calculated in the following boxes:

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As you can see your usage can calculate the range based off the values that you have already shoved in to other boxes and been calculated upon.

Remember, your SoH is important, you screw that one up and the flow on can cause some serious issues with the rest of the sheet.

Finally here is your charger and it's efficiency:
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Now I use charger loss, so I have "lost" 10% of it for my use, this means my charger is 90% efficient, but I'm a pessimist, I look at things negatively, so I went with loss instead of charger gain, so just invert your value.

So my 3kW charger only really delivers 2.7kW to the actual battery.

Now, another important one to go into is your electricity usage costs, as if you are charging your conversion ~99% of the time at home, rather than opportunistic free charging if available, you need to know these.

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Of note, the Changeover box is really only useful like me for those that use Grid Storage rather than Battery Storage, so you can ignore the changeover value.

So you'll need to grab your power bill and find your on-peak, off-peak and feed-in tariffs from it, and if you don't use grid storage, then ignore the changeover value. It has flow ons through the sheet, so rather than giving you a bunch of #DIV-0 errors, just leave it, unless you are happy with a heap of #DIV-0 errors.

Now the next section to play with is the running costs table:
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For this, I get paid fortnightly (Every 2 weeks) as do a lot of people I know, so we generally look at things in a pay period, or every 2 weeks. If you get paid weekly, multiply that by 2 and punch it in, if you get paid monthly, just halve your costs and punch that in.

For your registration you may have to look it up, in Australia we have all taxes and stuff included in the costs and I pay tax, I get no credits on them, so I just used the full value. I know in some countries there are Federal, State, Local and other taxes that you may have to find out in order to add these values fully.

This is not an accountants spreadsheet, and trying to make one that does every possible tax system in the world would be nigh on impossible, so you'll need to work these values out on your own.

Once you put in the 3 major boxes, ergo running costs, servicing, and registration, it will add them together and spit you out a daily running cost value for your ICE.

I understand there can be more costs here, however these are also shared by EV's such as Brake, Suspension, Tyres, etc so I do not consider them to be factors here. Plus most cars do not roll through those things yearly, rather being every 2-3 years some type of extra servicing will need to occur, and you'll still need to do suspension bushes and tyres on your EV.

I have tested the EV Registration box, entering a zero value into it does not seem to break the sheet.

Onto the next section, the cost of your conversion

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I have allocated 24 boxes in here, this gives you an idea of some of the things that will need to be factored into the conversion, you may have more, may have less, you may have to add some things together like Ancillaries and Consumables to fit it all into the given cells. Or if your spreadsheet-fu is good, just go changing things on me.

I know I have missed some things here, mainly because I don't yet know what they are going to cost me or how I am going to solve the problem (Dash readout, wheel speed sensors, etc) so I have the room to add them.

Now, onto the final part of the sheet:

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So here it shows me all the final values of everything, Cost of Conversion probably could have been shoved somewhere else in the page or moved, but I had it there and through my thinking, I left it there.

THE ONLY BOX YOU CAN CHANGE ON THIS PAGE IS YOUR DAILY RANGE, THAT IS HOW FAR YOU INTEND TO DRIVE THE CAR EVERY DAY

So here I see that I can now start breaking down the numbers even better.

I have to add another post under this however as I have hit the maximum number of pictures in one post.
 

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Discussion Starter · #2 ·
Ok, to go on with the breakdown:

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From here you can see that leading on from my previous post, the 10.08kWh of usage from the battery needs 11.088kWh to charge it back up.

Then I have broken down how much that costs you per day to charge that On-Peak, Off-Peak, Changeover, and Solar. If you charge direct off Solar, you are essentially saving that money, so I made it green. It's not really a cost, it's a saving.

So now it takes the values to run your ICE, and works out yearly how much it costs to run your EV, and then works out the savings, like so:
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And lastly, the dead final box to help you decide if this project is worth it to you and whether you see the timeframe as reasonable, as remember, you won't start saving straight away, you are now in the hole with this conversion, so any real savings will be deferred until the cost of your conversion is paid off by your savings

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As you can see, in my case, at this point in time, with my plans, I am looking at around 4.73-5.38 YEARS to pay off this conversion. Worth it to me? Yeah.

Worth it to you? Maybe not.

But for example, without showing all the working out and stuff, if I decided that I didn't want bodywork, interior, and a paint job, I can take those away from my costs, as they are wants and not needs, and it changes my values like so:

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So as you can see, if I am happy to drive around a car that looks like hot garbage (as my project does) then I can get away with 4.04-4.58 years, so I'll save myself 6 months on not doing those things.

Anyway, onto the links:

EV Conversion Calculator in ODS Format (Open Office)

EV Conversion Calculator in XLS (Microsoft Office)
 

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I mean, all calculations aside...Buying an EV or converting a gas car is not a good strategy for saving money on gas. It's cheaper and more efficient to keep the car you have going than to buy a new one, almost always.

If you're going to buy a new car anyway, then it can make sense to buy an EV, but like...I dunno what to tell you, a 2017 Chevy Bolt is $15k in the US, and it was $30k 3 years ago, and it probably won't go down much more than $5k for the next five, given the fact that any running/driving car that's safe and legal tends to go for $5-10k, not matter the age. Your stats above are marginal in the face of depreciation curves like that.

I don't mean to dog the effort, but instead of converting, buy a well-depreciated factory EV and sit pretty. Factor in that it's a dicey calculation to value a converted car vs an original car in the same condition, and it's just dubious to view conversion as anything but a substantial cost.

I converted my Mini because I wanted to look cooler than I did in my electric Smart Fortwo (and because I like building things)...
 

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Discussion Starter · #6 ·
I mean, all calculations aside...Buying an EV or converting a gas car is not a good strategy for saving money on gas. It's cheaper and more efficient to keep the car you have going than to buy a new one, almost always.
Oh wxa6, there's better strategies, however in my case, it's what I'm doing and I was curious if it would actually pay off in the long run. That wasn't my original intent, but it's good to know that I will pay it off, which is nice to know.

If you're going to buy a new car anyway, then it can make sense to buy an EV, but like...I dunno what to tell you, a 2017 Chevy Bolt is $15k in the US, and it was $30k 3 years ago, and it probably won't go down much more than $5k for the next five, given the fact that any running/driving car that's safe and legal tends to go for $5-10k, not matter the age. Your stats above are marginal in the face of depreciation curves like that.
AHH but see for that plan to work, you need to actually have a half reasonable second hand market of half reasonable EV's available.

Australia doesn't really have that, my wreck still cost $6,600

I don't mean to dog the effort, but instead of converting, buy a well-depreciated factory EV and sit pretty. Factor in that it's a dicey calculation to value a converted car vs an original car in the same condition, and it's just dubious to view conversion as anything but a substantial cost.
See that's the thing, they aren't greatly abundant here on the second hand market, and I know if exactly zero utes available as well. That'd part of why I'm doing mine.

I converted my Mini because I wanted to look cooler than I did in my electric Smart Fortwo (and because I like building things)...
Well there's no arguing a mini is cooler than a Merc...
 

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i love the calculations because we need to face the fact that, if we buy a $xx,xxx dollar economy electric car to drive (instead of say my 15mpg diesel truck), it will usually be years before savings are recognized. Sometimes upward of 10 years.
In my case, I think I got lucky. I found a 6000$ 2014 Fiat e500 with 47,000 miles on it. I offered to trade two motorcycles for it, maybe valued at 4200$. I had maybe 1400$ into the bikes, as both were either rebuilt by me or traded up by me. Then, the state of Oregon has a 2500$ cash rebate available. I have to keep the car for 2 years, is the main stipulation. After receiving that chunk of change, I’m now into the car negative money and can save $$$$ from the get go. I’m calculating I’m paying about 2 cents a mile with the 10 cents per kilowatt hour the electric company charges us for electricity. Vs. the 18-20 cents a mile the truck would use at 3.15$ per gallon for diesel...
 

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Well after installing a Soliton 1 years ago and blowing up 2 ADC9 motors, I'm still $17000 in the hole. That's considering taxes and insurance over 13 years in addition to all the hardware expenses. And certainly doesn't include any labor! With diesel at about $2.70 here and my current electricity rate around 12.8 cents/kw, I'm not saving a ton. If it hits $3-3.50/gallon that will help immensely! Regardless, it's fun to drive an EV.
 
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