Lifestyle
EV Basics – What’s a kilowatt hour?
So what’s a kilowatt hour or shall we ask Watts a Kilowatt hour?
As more car buyers take the plunge into owning an electric vehicle (EV), it’s important to educate on the EV specific units of measure which differ greatly than your traditional gas burning vehicle. What is a kilowatt hour? How does it differ from a kilowatt? And why does this even matter?
Background
First, let me preface everything by saying that much of what I’m about to write is based on US specific units of measure since that’s what I’m familiar with. For instance, miles vs km and US dollars versus Euros. I’m also over simplifying and breaking things down to basic laymen terms so please cut me some slack if you already know all this!
If you receive a utility bill for your residence then you should probably be somewhat familiar with, or have heard of, a kilowatt (kW) and kilowatt hours (kWh) since that’s what electricity bills are measured on. Your EV is no different and uses these same units of measure although it’s probably something you haven’t paid much attention to in the past.
kW and kWh Units
Depending on the EV display you may see watt hours (Wh) or kilowatt hours (kWh) in some places and watts (W) and kilowatts (kW) in others. The kilo or k is a standard prefix meaning a thousand. So 1 kWh is 1,000 Wh. If you own your EV long enough you may just get to the next level, megawatt hour (MWh) which would be one million Wh!
Now for the fundamental definitions:
kW is a measurement of power and kWh is a measurement of energy.
Energy is the amount of work that can be performed. kWh, calories, joules are all units of energy. A slice of pizza has 285 calories which is 0.33 Wh of energy that can be derived from that substance. Energy can be converted and change in form. For instance we can convert that slice of pizza to heat by setting it on fire. The fuel is the pizza, but don’t try converting it in your EV!
Power is the rate at which energy is generated or used. kW is a unit of power. When you accelerate in your EV you’re using power and when you decelerate with regenerative braking you’re generating power. The Model S dedicates half the speedometer display to the unit of power on the right side. There you can see how many kW you are using (indicator is orange) or generating (indicator is green) at any instance in time. It’s great to be able to see this however you can’t easily convert this into a cost. In order to do that, you’ll need to measure it over time and convert it into a unit of energy.
Power is similar to your speed. 50mph is your speed, but you have to maintain that for an hour to travel 50 miles. Similarly, 40kW is how much power you’re using and you’ll have to maintain that consumption for one hour to use 40kWh. If you spend half that hour at 40kW and the other half at 20kW you’ll end up consuming 30kWh. Power usage is constantly changing and will depend on driving habit as well as usage of onboard amenities such as your seat heaters or A/C unit.
A 100W incandescent light bulb used over 1 hour will consume 100Wh of energy. If you use that 100W bulb for 8 hours every day, it will consume 800W or 0.8 kWh per day. After 30 days, it will have consumed 0.8kWh x 30 = 24 kWh. After 365 days it will have consumed 292 kWh. Measuring your EV is done in a similar fashion but keep in mind that an EV can both use and generate power (regenerative braking) over periods of time. The difference or net power used (used – generated) is what you see reported on your EV display.
Units for Charging
Charging your EV you transfers energy back into your battery so you’re effectively storing kWh for later use. EVs report charging in different ways but the most common is to report by kW and kWh added. So a charge rate of 6 kW is storing 6kWh for every hour of charge. If you’re charging at 6kWh and charge for 2 hours you’ll have an extra 12kWh added at the end of your charge.
When it comes to driving, we’re trained to think in terms of miles, but not all miles travelled are the same when it comes to energy usage since there are variations in terrain and elevations. Weather also plays a factor for each mile travelled. A kWh stored, on the other hand, is always the same. The main difference is how you use that kWh.
The Model S offers the option to display charge rate by kW and kWh or by miles. Not surprisingly most Tesla owners choose to display charge rate in terms of miles. However it’s important to note that there’s a huge assumption being made about how many miles you can drive on a Wh and that assumption needs to account for charging efficiency. Tesla uses their proprietary algorithm to compute this value.
On Tesla’s online calculator they assume 300Wh/mile average use and a 90% charging efficiency. My own measurements show the average Wh/mile usage to be a bit higher (306 lifetime average) and the charging efficiency to be slightly less (81% last month).
What about Volts vs Amps?
Now you may be wondering how all this relates to volts and amps. This gets us back to the basics. One can calculate watts by multiplying volts with amps. W = V x A. So if you’re at a public charger and it’s charging at 199V and 30A (reference picture above), you’re essentially charging at 199V x 30A = 5,970W or about 6kW. This equates to 6kWh added after an hour of charging, but as we all know this is based on an ideal world where it charges at 100% efficiency with no loss. At 199V and 30A, the Model S is reporting this as a rate of 16 mi/hr.
Lets check that math:
5,970W/300Wh/mile standard assumption = theoretical 20 miles/hr charge rate. But that doesn’t account for charging efficiency. The Model S is reporting 16 mi/hr so its assuming an 80% charging efficiency (16/20) under these conditions.
Cost
Utility bills price per kWh. Your electric company may break it down by distribution vs generation, time of use, etc. and then associate a different cost per kWh on each pricing tier. It seems complex but you can simplify this.
To figure out your total cost per kWh just take your total amount of the bill and divide it by your total energy usage for the same period. That may include the various service fees, taxes, etc. but in the end you’re paying the electric company that total amount for those kWh regardless of what it’s derived from. Knowing this will help you calculate the costs for your road trips based on the kWh used.
Summary
Elon Musk
Tesla FSD is about to know your specific house and neighborhood better than any map
Tesla confirmed it is building a feature that lets you teach your car where to go.
Tesla is building a feature that will let drivers talk to their car in plain language and teach it exactly what to do, with the vehicle remembering those instructions for every future trip. Tesla VP of AI Software Ashok Elluswamy confirmed it this week on X after a user pointed out one of FSD’s most persistent real-world limitations is that the system has no way to receive contextual instructions the way a human driver would.
“FSD would be twice as useful in neighborhoods if I could actually talk to the car and tell it which driveway to pull into, the same way I would with a person driving me home. Right now, there isn’t really an input for telling Tesla what color the house is or giving it specific context like that. Google Maps is also notorious for putting pins on houses that aren’t actually yours.” Tesla owner Chris further noted, “It would be so cool if I could talk to the car while going down my street and say something like, ‘It’s the white house on the left, just past that SUV,’ and then have FSD remember that for next time.”
FSD would be twice as useful in neighborhoods if I could actually talk to the car and tell it which driveway to pull into, the same way I would with a person driving me home.
Right now, there isn’t really an input for telling Tesla what color the house is or giving it specific…
— Chris (@ChrissGPT) July 8, 2026
This feature would carry more weight than it might seem. Grok has been available inside Tesla vehicles since July 2025, expanded to European vehicles in February 2026, and gained a hands-free “Hey Grok” wake word with location-based reminders and natural-language navigation in the Spring 2026 update. But up to this point, Grok has had no authority over how FSD actually drives. Lane changes, braking, speed, and parking maneuvers remain entirely within FSD’s autonomous decision-making loop. What Elluswamy confirmed is that the next step pushes Grok into a supervisor role, one that translates spoken intent directly into driving decisions.
Tesla teases greater Grok FSD integration and ‘Banish’ feature ‘in about 3 months’
Elluswamy acknowledged at a January 2026 conference that while fully integrated voice control is on Tesla’s roadmap, “it opens up an entire area of testing that we have to do. For example, you shouldn’t be able to tell the car to crash, and it shouldn’t crash.” Elon Musk subsequently confirmed on June 23 that Grok voice commands will pass to FSD’s planning layer by September 2026, a three month timeline from confirmation to deployment.
The deeper significance is what this does for Tesla’s AI training flywheel. Every time an owner corrects FSD with a spoken instruction and the car learns and remembers it, that interaction becomes a data point covering an edge case that no simulation or scripted test could have generated. A fleet of millions of Tesla vehicles crowdsourcing hyper-local contextual knowledge, which driveway, which gate entrance, which side of the street, builds a layer of geographic and behavioral intelligence that competitors without a comparable fleet simply cannot replicate at the same speed or scale.
As Teslarati has reported, Tesla’s Cybercab and robotaxi operations have expanded to Miami following the Austin launch, with rider profiles already collecting preference data. Voice-taught contextual instructions linked to individual rider profiles means a Cybercab could eventually know before it arrives exactly which entrance to use, where to wait, and how to navigate the final hundred feet of any trip it has made before.
Lifestyle
Tesla app update makes Robotaxi ownership make a lot more sense
Tesla’s app now shows a live indicator when your car is actively driving itself.
A recent Tesla app update, released last week (4.58.5), gives visibility on whether a vehicle is navigating in its semi-autonomous mode or being drive by a human driver. The updated app now displays a live “Self-Driving” indicator in bright blue text directly beneath the vehicle’s speed readout whenever Full Self-Driving is actively engaged, along with the signature glowing blue navigation path that FSD users see on the main touchscreen. It is a small visual update with meaningful implications for how Tesla owners monitor their vehicles remotely.
The feature was first spotted in the wild by X user Jordan Camina, who shared video of a Hardware 3 Model S displaying the new animation through the app while driving. That detail is significant because it confirms the update is not limited to newer HW4 vehicles. It works across hardware generations, and Tesla confirmed it will eventually support all vehicles regardless of chip platform once both the app and vehicle software are updated. The vehicle side requires software version 2026.20.6.1, which has reached nearly 40% of the fleet so far, as monitored by NotaTeslaApp.
The feature makes the most practical sense when viewed through the lens of Tesla’s expanding robotaxi operation. In a robotaxi context, the owner of a vehicle generating ride revenue has a direct financial and safety interest in knowing whether their car is operating under autonomous control at any given moment. The app’s new FSD indicator gives fleet owners exactly that visibility, the same way a logistics company monitors whether a delivery driver is following the planned route. It also carries implications for Tesla’s insurance model. Tesla’s own insurance product prices premiums in part based on FSD engagement rates, and real-time visibility into when FSD is active creates a feedback loop that could eventually tie directly into policy pricing. For individual owners who have opted their personal vehicles into the robotaxi network, the update effectively turns the Tesla app into a fleet management dashboard, one that tells you whether your car is earning money, whether it is driving itself to do it, and whether everything is operating the way it should from wherever you happen to be.
Tesla expands Robotaxi to Florida, marking its third state for autonomy
As Teslarati has reported, Tesla launched unsupervised robotaxi rides in Miami this summer, a milestone that makes a remote FSD status indicator significantly more practical than a cosmetic feature. When a vehicle is operating as a robotaxi without a driver present, the owner or fleet operator needs a reliable way to confirm autonomy is engaged. The app now provides exactly that.
As noted by NotATeslaApp, The update also arrived alongside a hint buried in the same app version that Tesla plans to use the cabin camera to verify driver identity before FSD can be activated. Pairing identity verification with a live autonomy status indicator points toward the infrastructure Tesla is building for a fleet of driverless vehicles that owners can monitor the way you would track a package delivery.
Elon Musk
The Boring Company just doubled its tunneling power in Nashville
The Boring Company’s Prufrock MB2 is commissioned and ready to mine beneath Nashville’s streets.
The Boring Company’s second tunnel boring machine, Prufrock MB2, is officially ready to dig in Nashville. The company confirmed the news on X, posting: “Prufrock-MB2 is ready to mine in Nashville! MB2 commissioning is complete, including the brief 11 rpm rotation shown here. Will MB2 catch up to MB1, who had quite the head start? And Prufrock-MB3 ships in August!”
MB2 arrives with meaningful improvements over its predecessor. Lessons learned from the launch and operation of MB1 have already been applied to MB2 to improve efficiency and prepare the machine for launch.
Traditional tunnel boring machines operate in a stop-and-go cycle, digging roughly five feet, halt, erect precast concrete segments to line the tunnel wall, then resume. That repeated interruption is one of the main reasons conventional tunneling is slow and expensive. Prufrock is designed to install the tunnel liner simultaneously with mining, eliminating the need to stop every five feet. The machine also skips the need for excavated launch pits. Prufrock arrives on a truck, tilts down, and launches into the ground within 24 hours. And when the tunnel is complete, it emerges from the ground and drives to its next launch site on a trailer, eliminating the need for expensive cranes or pit excavation. The machine is also fully electric and runs with zero people in the tunnel during normal operations, controlled remotely from a surface operations center.
Prufrock-MB2 is ready to mine in Nashville! MB2 commissioning is complete, including the brief 11 rpm rotation shown here.
Will MB2 catch up to MB1, who had quite the head start?
And Prufrock-MB3 ships in August! pic.twitter.com/TTrMql2aRg
— The Boring Company (@boringcompany) June 17, 2026
It won’t be long before we hear of another major update on The Boring Company’s Music City Loop project – a planned underground transit network beneath Nashville that would move passengers in electric vehicles through a series of tunnels at highway speeds, and bypassing surface traffic entirely. Nashville was selected in part because of its strong rock conditions that suits the Prufrock machines well, and relatively less regulatory hurdles.
Progress has been steady on multiple fronts. All 37 permits and approvals required ahead of tunneling have been obtained, out of 45 total. Key wins include a fully executed TDOT tunnel permit authorizing 25 miles of tunnel, unanimous airport authority approval for a Nashville International Airport station, and the city’s first residential station agreement serving downtown tower residents.
With MB1 already tunneling, MB2 now commissioned, and MB3 shipping in August, Nashville is becoming something of a live proving ground for scaled tunnel boring. The broader ambition is not limited to one city. The Boring Company’s stated goal is to make underground transportation a practical alternative to surface roads across major metro areas. Nashville is one of many cities, including a successful Las Vegas tunnel system, where that idea is being put to the test at real speed.
Tesla shows rapid teardown of Model S and X lines, paving the way for Optimus at Fremont
Elon Musk admits he was ‘clearly wrong’ about Anthropic
