– Ben Martens

Tesla FSD Review

Welcome to another Tesla Tuesday!

Every Tesla comes with “Autopilot” which I roughly explain to people as cruise control for steering. It will keep you in your lane, keep you at the speed limit unless traffic slows, etc. In contrast to other car manufacturers, this works on any road in a variety of conditions.

There’s a step up from Autopilot called “Full Self Driving (Supervised)” which expands the capabilities to give you end to end self-driving. It will navigate, obey stop lights and stop signs, change lanes on the highway, etc. All Teslas are capable for this, but you must pay a $12,000 fee to enable it. As you can imagine, very few people are willing to pay that much, so they also offer a $200/month subscription that you can turn on and off. That was almost low enough to get me to try it out on our big road trip, but it was still too much to justify. (As I was working this draft, Tesla lowered the price to $100/month!) So I was happy when Tesla gave all Tesla owners a free month of FSD in April! We’ve put over 40,000 miles on our car without the FSD package so it has been interesting to see the differences.

The obvious question is: is it worth $12,000? And to that I immediately say “Nope.” It’s certainly more than a party trick, but I cannot fathom paying that much for it in my current situation. I’d probably pay $1000-2000 for it, or I would pay a bit more if the FSD capabilities stayed for future Tesla purchases.

With that said, this works shockingly well. Elijah’s school is 18 miles away and I literally had it drive us from our driveway to the school parking lot without me ever disengaging it. This included a mix of interstate, two lane highway, and side streets in rush hour traffic. This feature is no joke.

Note that they make it clear that you are still responsible for the car. You have to always keep your hand on the wheel and be ready to take over if something is incorrect. Once you’re in the car, it will scream at you and even pull over and stop driving in the extreme case where you really stop paying attention.

It’s not all roses though. While it will get you there safely and legally, it does make some awkward decisions. On our road trip to Oregon, it would change lanes when I would have been more polite and waited for a bigger gap. Or if someone is waiting to pull out of a side street in slow traffic, I might tap the brakes a bit to let them in. Or if the speed of a side street was 35, it might not speed up to 60 on the highway until the end of hte onramp. There are a few tuning options and I found “chill” with “minimal lane changes” to be closest to my driving style. I preferred it to be dumber and let me hint at things like lane changes (by turning on the turn signal.)

The FSD package also includes a couple extra goodies.

  • Automatic Parking – As you drive through a parking lot, it will see open parking spaces. You can tap one on the screen and it will back into the spot. This does work but sometimes it takes a couple attempts to get in straight. I would expect it to just nail it on the first time, especially in a wide open parking lot.
  • Smart Summon – Let’s say it’s raining when you come out of the store and you’re debating running to the car. With Smart Summon, you just press a button on your phone and your car will come to you. This only works on private roads and it drives awkwardly slow, but it does work. It’s a bit creepy to see your big investment driving itself with nobody behind the wheel. This one definitely feels like a party trick, but supposedly there is an improved version coming which they call “Actually Smart Summon”.

So yes, this technology is mind-blowing. I have no doubt that this will work flawlessly in the future. But for now, I’m quite content with the default Autopilot capabilities. The price for the full package is very aspirational right now. However, now that the monthly price is $100/month, I’d strongly consider doing that for a long road trip.

Here’s a short demo of it in action in our car. If you get bored with the regular driving part, you can skip towards the end to see the self-parking and the smart summon features in action.

Martens Memorial Day 1995

Our final installation in the series of videos from our Memorial Day family gatherings is from 1995. It looks like this Uncle Dean and Aunt Sandy’s family couldn’t come and apparently we didn’t take out the camera much. Most of the tape was a science show that Ryan and I recorded. We had quite a few different experiments with explanations of the science behind each one. I have mercifully cut most of that out of this quick recap for you.

Here is a quick reference list for all the YouTube videos:
Memorial Day 1990
Memorial Day 1991
Memorial Day 1993
Memorial Day 1995

Six Handed Easter Piano

As one of the three people at church who play for our services, I was asked to participate in a “six handed piano” piece. I’ve heard of duets but a trio!? It ended up being challenging in ways I never expected: it’s hard to physically fit 3 people at a piano! I suppose it depends on the specific music being used, but ours was very tight and we had to bend our wrists awkwardly, share keys, and overlap hands. We played this at the close of the Easter service, and despite it having one of the highest mistake rates of any of our practices, it was well-received. The video below was taken during one of our practices when I mounted a camera overhead. (That’s me on the left trying my best to keep up!)

Telsa Model Y – 40,000 Mile Review

Welcome to another Tesla Tuesday!

We just crossed 40,000 miles on our 2022 Model Y after almost exactly two years of ownership. I’ll use a similar format to the 20,000 mile review.


While I’ve always been interested in EVs as technology, I was never willing to pay extra to get it. The key reason we jumped into the Tesla was because I believed we could break even on the cost. I have a detailed data pipeline set up to track everything I can about our costs. By tracking the prices of gas stations around my home daily and comparing it to how many miles we drove each day, I can calculate that we would have spent $8,047 on gas using the Ford Escape that we would likely have purchased instead of the Model Y. Instead, we have spent $1,722 on electricity for charging.

  • 91% of the charging was done at home for $0.11/kWh
  • 7% of the charging was done at super chargers on road trips for around $0.40-0.45/kWH
  • 2% of the charging was done at free chargers like Airbnb’s

Based on the prices of the Model Y and the Escape when we bought our car, I estimated that we would need to save $18,000 to break even. The bulk of that savings is going to come from not buying gas which means that the more gas costs, the faster we break even. Here’s a chart showing the daily gas prices for the half dozen stations closest to our house (which includes a Costo gas station.)

Based on the data so far, I estimate that we’ll save about $15,000 in gas in the first 100k miles if gas prices stay in the same range.

A big chunk of the rest of the savings should come from reduced operating and service costs. There are no oil changes or brake replacements and there are a lot fewer moving parts to wear out. Up until a few weeks ago, we hadn’t bought anything more than windshield washer fluid for the car. But we did buy tires so that was a major purchase. As a quick update to that tire post, the new tires have been working out well. Efficiency was a major part of my research and while it’s difficult to tell over just the first couple thousand miles, I’m not seeing anything that indicates a measurable decrease in efficiency.

I do think that state registration fees are hurting us more than I expected. Our area keeps voting in more and more taxes so, for example, we spent $939 to register the Tesla in 2023. A large portion of that price is based on how much the state says your car is worth so having the extra value in the car does mean it’s $100-200 more/year than Escape would have been.

A major repair bill with the Tesla could change everything, but at this point we’re on track to “break even” even with pessimistic calculations. For example, my $18,000 goal assumes that we the Tesla and the Ford would have lasted the same number of miles and would have sold for the same amount of money. I’m hoping our Tesla will last longer than the Ford would have and I also expect it to sell for significantly more given the longevity of EVs.


I’m not going to redo all the stats that I did in the 20k update, but I’ll share a new stat: Battery Health. The TeslaMate software which gives me so much of the data I use to track these costs has a new calculation for battery health. It tries to estimate the actual capacity of your battery against the capacity it had when it shipped. This is not an exact measurement, but it shows that we’re right on track with the expected degradation curve. After 40,000 miles we’ve lost 3.6% of our usable capacity. I did notice during our trip to Utah that there was more degradation, but the numbers have bounced back. I’m not sure if that’s something due to us doing lots of rapid charging or driving in extreme heat at high speeds, but it doesn’t look like anything to worry about. Tesla says that batteries lose about 5% in the first 25,000 miles on their way to losing 12% over the first 200,000 miles.


The best way to explain our thoughts about this car is that if something happened to it today, I’d pull out my phone and buy another one without much thought. We love this car! Yes, it’s a bit annoying looking like so many other cars on the road, but other than that, it’s a fantastic car to own and drive. We drive this almost exclusively now and I must keep track of the last time I drove the truck so it doesn’t sit too long.

I’ve probably said this before, but I underestimated how wonderful it is to walk out to a “full” car every morning. I always thought that filling up with gas didn’t take that much time so it wasn’t a big deal, but you know what takes even less time? Doing nothing! We pull into the garage, plug in the car and that’s it. It’s full every morning.

I also love the “golf cart” nature of the car. I just hop in and go. There’s no consideration about whether I’ve run the gasoline engine long enough to recharge the 12v battery, burn off the moisture I’m generating in the exhaust system, get all the engine parts fully lubricated, etc.


The EV market has changed a lot since we bought our car. The Model Y is now the best selling car of any kind on the planet. It sold 1.23 million units in 2023 beating out things like the Corolla and the Rav4. Not only that, but it was an increase of 66% over the previous year. Tesla factory capacity continues to expand, but estimates for 2024 are all over the place as they are seeing slowdowns like (but smaller than) the rest of the auto industry. 1 in every 12 cars sold in the US is full battery electric. Furthermore, prices on the Model Y have decreased significantly since we purchased and there are federal tax credits at play too. At this point, we love the car so much we’d probably pay a premium to get it, but it’s nice to know that the EV/gas comparison will be more lopsided in the EV’s favor. And it’s even nicer to know, that given our flawless track record with the car so far, we hopefully have a ton of miles left before we start thinking about the next car.

Martens Memorial Day 1991

Last week I posted about our family Memorial Day celebrations from 1990, and now I finished editing another one. There are four of these total so I’ll see if I can do one a week. This next one is from 1991 and it was a year when it was warm enough to go swimming. It probably wasn’t very warm, but it was enough for us to enjoy swimming with cousins.

Martens Memorial Day 1990

When I was growing up, Memorial Days were a ton of fun. Most of Dad’s side of the family would get together at our house (about 20 people.) Some years it was warm enough to swim while other years we’d have cold and rain, but we would always have fun. For a few of the years, we had a video camera. The footage is far from stellar, but I stumbled on a digitized copy recently and decided to edit it down. Don’t expect a masterpiece, but it brings back fun memories for me as I watch it. There are some more that I’ll get around to editing and posting down the road.

Model Y Tire Research

Welcome to another Tesla Tuesday!

After almost 40,000 miles, the time has come to break the streak of spending $0 on service and maintenance (other than windshield washer fluid.) We’re probably replacing the tires a tad bit early, but they’re down to under 5/32″ in some places and at that point the tire shops stop doing repairs, etc. And since I regularly watch my wife and child drive off in the car, I feel better knowing they can stop quickly when they need to. 40,000 miles seems light to me for tire wear, but reading experiences from other users, it sounds like we did average/well on the stock tires. The cars are heavier and very sporty so it’s easy to burn through the performance tires.

Shopping for tires on our Tesla Model Y was an interesting experience. For example, I’ve never really considered rolling resistance of a tire before. Sure I know that some tires are marketed as more efficient than others, but since Teslas have such detailed economy measurements, I was able to find specific percentage differences in various tires. The challenge is that those measurements were mostly self-reported and varied widely in believability.

The second surprise was being reminded that we are effectively drive a sports car. It can do 0-60 in 4.7 seconds (or 4.2 if you swipe your credit card) and those tires are more expensive than what we bought for our Escape or Impreza.

The third surprise was just how much prices have increased since we last purchased tires in 2019. As I was shopping, I kept getting sticker shock at the total installed price. I got the idea to look up our receipt from 2019, find those exact same tires, and then compare the price. It turns out that the same set of tires from 2019 would have cost 27% more if we bought them now. So add that to the fact that these sportier tires were more expensive than the previous tires (an extra ~$90/tire) and that explains the sticker shock. I did check out Costco and was initially going to use them, but I ended up picking a tire that they didn’t offer. I found their tire prices similar but their installation and warranty was much cheaper.

In the end, I chose the Hankook iON evo SUV tires. They’re less performant than other popular options but offer longer tread life. I also got an alignment done because the initial tires were more worn on the inside than on the outside.

Time will tell how well these new tires hold up. It will come as no surprise to you that I was have an absurd amount of data to eventually compare their efficiency with the stock tires.

Google Pixel 7a Upgrade

We usually try to keep our phones 2-3 years, but even though we just got our Pixel 6a’s ~12 months ago, we’ve upgraded. I was having some oddities charging my phone sometimes and Tyla had trouble with the fingerprint sensor with one of her hands. Neither was a major problem, but I noticed that the 7a’s were on sale for $370 and our 6a’s were worth $200 on trade in. So for $170 per phone, we could upgrade. Why not? The 7a is a pretty big jump from the 6a in that it has face unlock, wireless charging, and an even better camera. We only paid $300 for our 6a’s so they basically cost us $100 for a year of use.

Even after a year of usage, the batteries on our phones were easily lasting through the day and the pictures that it took were gorgeous. I’m still a very big fan of the Pixel “a” line of phones. I would wager that if you had Pixel 7a and a flagship $800-$1000 device, most people couldn’t tell the difference. The only thing that might tip them off is screen size, but personally, I’m not a fan of the gigantic phones. I want someting that easily fits in my pocket. The 7a is exactly the same dimensions as the 6a, but don’t worry: they moved the buttons about 1 mm so you have to buy new cases.

If you’ve been on the fence about trying out the Pixel *a lineup, expect to see more sales on them as we get closer to the next batch of phones being released. I expect to see them on sale in the $300-325 range over the next few months. They’re fantastic devices and the cameras in them rival any phone at any price.

As is the norm when we upgrade devices, here’s an updated device history:

Sanyo SCP-4000 (?)
May 2001
LG 4500
April 2004
Motorola Q
September 2006
HTC Touch
May 2008
HTC Touch Pro 2
January 2010
HTC Trophy
June 2011
HTC 8x
December 2012
Nokia Lumia Icon
January 2015
Samsung Galaxy S7
October 2016
Google Pixel 4a
September 2020
Google Pixel 6a
March 2023
Google Pixel 7a
February 2024

EV and ICE Efficiency

Welcome to another Tesla Tuesday! Maybe this is more of “EV Tuesday” but we’ll go with it.

Let’s talk about energy efficiency. We know that 30-40mpg is good for an ICE (internal combustion engine) vehicle. But how good is it when you consider all the available energy in the gasoline? The EPA says that a gallon of gasoline is equal to 33.7 kWh. That’s a huge amount of power but the engine only converts 25-30% of that into useful energy. The vast majority of the energy in gasoline is lost to heat.

To put that amount of energy into perspective, there’s theoretically enough energy in a gallon of gasoline to power our house (minus EV charging) for 1.5 days. When full, my F150 has almost a megawatt of power in the gas tank!

EVs on the other hand are more like 80-90% efficient. That can vary more widely though because, for example, in cold weather, heat isn’t free like it is in an ICE vehicle, so you have to use extra energy to generate heat. In an ICE vehicle you’re generating way too much heat year-round whether you want it or not.

Our Model Y LR is one of the most efficient EVs you can buy, and over the first 37,000 miles, it has averaged 278 Wh/mi (Watt hours per mile) or 3.59 miles/kWh. With the energy in one gallon of gas, it could go 121 miles.

This is exactly how the EPA generates their MPGe metric. It’s a bit of a silly calculation because you’re never going to build a car that can extract 33.7 kWh from a gallon of gasoline, but I think it is useful to understand how all those calculations work. And when you hear about how efficient a particular car is, remember that 70% of the energy it’s consuming is lost as a byproduct.