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I build off-grid camper vans for a living and install solar + lithium battery systems regularly. The technology has matured a lot in the last few years. What us

by ronb1964 6mo ago

I build off-grid camper vans for a living and install solar + lithium battery systems regularly. The technology has matured a lot in the last few years. What used to take a massive roof array and a bank of heavy lead-acid or AGM batteries to run basic appliances now fits in a fraction of the space with lithium. The limiting factor in real-world installs isn't the panels or the batteries anymore, it's getting customers to right-size the system for their actual usage instead of what they think they'll use. People consistently underestimate idle draws and overestimate how much sun they'll get. Scale that mindset problem up to a national grid and I imagine the challenge is the same.

ryzvonusef 6mo ago
there is a youtube video I watched where an RV guy converted as many appliances and gadgets on his vehicle to Direct DC as he could, saved a lot on wastage from DC-AC-DC conversions. We need mundane home DC solutions.
- jabl 6mo ago
  There's https://currentos.org/ https://currentos.org/ working on it.
  - ryzvonusef 6mo ago
    Thank you for sharing! that's an interesting project.
morphle 6mo ago
I build off-grid electrical campers (Mercedes eSprinter) with extended 600kWh batteries (11 times more battery capacity than the default model) and charge them from solar panels at home. I disagree with your negative mindset, people who ride in my eCamper quickly learn you can go 100% solar and use you camper at home to store all neighborhood solar and even charge other EVs from our eCamper battery. We make our own parallel battery cell dis/charger to extent the LFP battery life to 20000 charges (one a day for 50 years).
- RobinL 6mo ago
  Wow, that's big! I'm curious, how much does the 600kWh battery cost nowadays? Amazing that the tech has got to a point this is even possible
  - morphle 6mo ago
    15kWh 48V LFP battery around $1800 with low quality battery management system in metal box on wheels. Car batteries need more expensive inverters if you want to fast charge them (150kW-950kW) and super fast discharge them while driving fast (>100 kW). Thus my 600kW extender comes to almost $62000 for vans and small trucks. Cheaper if installed as house battery. The Mercedes eSprinter 56kW van costs around $80000 new but we sell 3 year old vans like this for $4000 without battery. So refurbished and converted to eCamper with 1800 mile range you pay $6700. You can drive 3000 km (almost 1860 miles) with this battery in the eSprinter and eCamper. A normal size car would go twice as far with this battery but it's big and heavy enough that you need to tow it in a trailer. The crucial point though is the charging/discharging inverter (converter) that I purpose built (printed circuits boards) and a change to the car firmware. Without it the car will reject the battery, your acceleration would be less and it also would not last the same amount of discharge cycles. My battery electronics works fine for cars, trucks, boats, house and neighborhood batteries (up to 6mW per shipping container). We build entire smart grids around the batteries, solar panels and tiny houses. https://www.researchgate.net/profile/Merik-Voswinkel/publication/309254511_Fiberhood_Smart_Grid/links/5807410c08ae5ad1881691e3/Fiberhood-Smart-Grid.pdf https://www.researchgate.net/profile/Merik-Voswinkel/publica...
    - RobinL 6mo ago
      I love this! Thanks for the detailed response, super interesting
      - morphle 6mo ago
        Thank you. I hardly get to explain the techology I 'invent' (power chips, power router, parallel battery charger, car firmware, charging (station) software, simulation software) because the investors customers only want to hear that its cheaper or sells better (then Tesla). Or that besides going from 4000 to 20000 dis/charge cycles you also prevent any li-ion fires and have fire alarm sensors on every battery cell. The main thing I would like to shout from the rooftops is: Not a single battery on the planet charges their battery cells in parallel as we do, they all shorten their cell lifetime by charging/discharging them to fast in series, what will damage all battery cell types but especially the li-ion. It is the same with the article we are commenting on here: if people just listen to the statistics, the simulations and the actual market developments they would see that 100% solar+battery is the cheapest energy. The simple message is Solar is by far the cheapest energy: below 1 dollar cent per kWh and that will fall a lot more in the next decade until we get to 'a squanderable abundance of free and clean energy' as Bob Metcalf puts it https://www.youtube.com/watch?v=axfsqdpHVFU https://www.youtube.com/watch?v=axfsqdpHVFU Batteries still double the cost of that solar but these prices are falling rapidly too. It is already cheaper to have solar nearby than transmit it over a distance of a few miles. More in my earlier comments weeks and months ago https://news.ycombinator.com/threads?id=morphle https://news.ycombinator.com/threads?id=morphle
gpm 6mo ago
I doubt that issue scales to the national grid at all... national grids tend to dictated in size by more or less market forces not careful pre-planning... and capacity planning for new projects tends to have actual data about energy demand and weather patterns and so on.
- ViewTrick1002 6mo ago
  And what the market doesn’t solve the grid operator solves using ancillary markets.
jacquesm 6mo ago
Very nice. I have my eyes on Lithium-Titanate cells for my house, I can't wait until they go down in price enough. Weight and energy density are not an issue, but safety is and those cells are very good in that sense. https://en.wikipedia.org/wiki/Lithium-titanate_battery https://en.wikipedia.org/wiki/Lithium-titanate_battery
- turtlebits 6mo ago
  LFP is safe and is under $100/kwH.
hvb2 6mo ago
> Scale that mindset problem up to a national grid and I imagine the challenge is the same. Except that we have raw data there? The only question is how fast it grows, but since we're transitioning that's mostly a question of how fast you decommission fossil plants.
- entropicdrifter 6mo ago
  Yeah, agreed. It's a lot easier to be empirical when the scale of the requirements is quite literally unimaginable without just dealing with raw numbers.
  - lazide 6mo ago
    Germany’s renewables rollout would like a word….
    - hvb2 6mo ago
      If you mean what they started in the 90s? That's not what this is about. The conversation was about not being able to rightsize today. Germany did jumpstart their market successfully but that was in a wildly different time. Want to talk about what a typical KWp of installed solar cost at the time? Hindsight....
      - lazide 6mo ago
        Germany has only a tiny portion of their total energy needs on renewables - if we’re being honest about the definition of ‘total energy needs’. Like in the camper van scenario, if we include winter heating and transportation? Oh boy. It’s getting better, but if we’re really honest very far from the truth
turtlebits 6mo ago
While I agree with underestimating capacity, the problem only really applies to off grid. For regular homes, it just means less savings.
- lazide 6mo ago
  It means some other infrastructure (fossil fuels?) needs to take up the slack, and people underestimate actual costs at larger scales. It’s the big issue in Germany for instance - it’s all fun and games until Winter.
  - pixl97 6mo ago
    And? Any coal not used in summer is coal not dug up.
  - turtlebits 6mo ago
    Which is fine, since you're still reducing your reliance on the grid. However, when you're off grid, underestimating capacity means your SOL and need to buy a generator and burn fuel on-site.
  - uecker 6mo ago
    Germany has more wind in winter, so traditionally has more production of renewables in winter months.
    - lazide 6mo ago
      It has dramatically higher thermal heat demands in winter - far higher than is compensated for by that. Even if everyone switched to heat pumps.
      - uecker 6mo ago
        True, but higher demand for heating in winter is not specific to Germany. In the end, Germany will likely need to import energy anyway - just as it does today. But this means this question may not be the most relevant.

ryzvonusef 6mo ago

there is a youtube video I watched where an RV guy converted as many appliances and gadgets on his vehicle to Direct DC as he could, saved a lot on wastage from DC-AC-DC conversions. We need mundane home DC solutions.

jabl 6mo ago
There's https://currentos.org/ https://currentos.org/ working on it.
- ryzvonusef 6mo ago
  Thank you for sharing! that's an interesting project.

morphle 6mo ago

I build off-grid electrical campers (Mercedes eSprinter) with extended 600kWh batteries (11 times more battery capacity than the default model) and charge them from solar panels at home. I disagree with your negative mindset, people who ride in my eCamper quickly learn you can go 100% solar and use you camper at home to store all neighborhood solar and even charge other EVs from our eCamper battery. We make our own parallel battery cell dis/charger to extent the LFP battery life to 20000 charges (one a day for 50 years).

RobinL 6mo ago
Wow, that's big! I'm curious, how much does the 600kWh battery cost nowadays? Amazing that the tech has got to a point this is even possible
- morphle 6mo ago
  15kWh 48V LFP battery around $1800 with low quality battery management system in metal box on wheels. Car batteries need more expensive inverters if you want to fast charge them (150kW-950kW) and super fast discharge them while driving fast (>100 kW). Thus my 600kW extender comes to almost $62000 for vans and small trucks. Cheaper if installed as house battery. The Mercedes eSprinter 56kW van costs around $80000 new but we sell 3 year old vans like this for $4000 without battery. So refurbished and converted to eCamper with 1800 mile range you pay $6700. You can drive 3000 km (almost 1860 miles) with this battery in the eSprinter and eCamper. A normal size car would go twice as far with this battery but it's big and heavy enough that you need to tow it in a trailer. The crucial point though is the charging/discharging inverter (converter) that I purpose built (printed circuits boards) and a change to the car firmware. Without it the car will reject the battery, your acceleration would be less and it also would not last the same amount of discharge cycles. My battery electronics works fine for cars, trucks, boats, house and neighborhood batteries (up to 6mW per shipping container). We build entire smart grids around the batteries, solar panels and tiny houses. https://www.researchgate.net/profile/Merik-Voswinkel/publication/309254511_Fiberhood_Smart_Grid/links/5807410c08ae5ad1881691e3/Fiberhood-Smart-Grid.pdf https://www.researchgate.net/profile/Merik-Voswinkel/publica...
  - RobinL 6mo ago
    I love this! Thanks for the detailed response, super interesting
    - morphle 6mo ago
      Thank you. I hardly get to explain the techology I 'invent' (power chips, power router, parallel battery charger, car firmware, charging (station) software, simulation software) because the investors customers only want to hear that its cheaper or sells better (then Tesla). Or that besides going from 4000 to 20000 dis/charge cycles you also prevent any li-ion fires and have fire alarm sensors on every battery cell. The main thing I would like to shout from the rooftops is: Not a single battery on the planet charges their battery cells in parallel as we do, they all shorten their cell lifetime by charging/discharging them to fast in series, what will damage all battery cell types but especially the li-ion. It is the same with the article we are commenting on here: if people just listen to the statistics, the simulations and the actual market developments they would see that 100% solar+battery is the cheapest energy. The simple message is Solar is by far the cheapest energy: below 1 dollar cent per kWh and that will fall a lot more in the next decade until we get to 'a squanderable abundance of free and clean energy' as Bob Metcalf puts it https://www.youtube.com/watch?v=axfsqdpHVFU https://www.youtube.com/watch?v=axfsqdpHVFU Batteries still double the cost of that solar but these prices are falling rapidly too. It is already cheaper to have solar nearby than transmit it over a distance of a few miles. More in my earlier comments weeks and months ago https://news.ycombinator.com/threads?id=morphle https://news.ycombinator.com/threads?id=morphle

gpm 6mo ago

I doubt that issue scales to the national grid at all... national grids tend to dictated in size by more or less market forces not careful pre-planning... and capacity planning for new projects tends to have actual data about energy demand and weather patterns and so on.

ViewTrick1002 6mo ago
And what the market doesn’t solve the grid operator solves using ancillary markets.

jacquesm 6mo ago

Very nice. I have my eyes on Lithium-Titanate cells for my house, I can't wait until they go down in price enough. Weight and energy density are not an issue, but safety is and those cells are very good in that sense. https://en.wikipedia.org/wiki/Lithium-titanate_battery https://en.wikipedia.org/wiki/Lithium-titanate_battery

turtlebits 6mo ago
LFP is safe and is under $100/kwH.

hvb2 6mo ago

> Scale that mindset problem up to a national grid and I imagine the challenge is the same. Except that we have raw data there? The only question is how fast it grows, but since we're transitioning that's mostly a question of how fast you decommission fossil plants.

entropicdrifter 6mo ago
Yeah, agreed. It's a lot easier to be empirical when the scale of the requirements is quite literally unimaginable without just dealing with raw numbers.
- lazide 6mo ago
  Germany’s renewables rollout would like a word….
  - hvb2 6mo ago
    If you mean what they started in the 90s? That's not what this is about. The conversation was about not being able to rightsize today. Germany did jumpstart their market successfully but that was in a wildly different time. Want to talk about what a typical KWp of installed solar cost at the time? Hindsight....
    - lazide 6mo ago
      Germany has only a tiny portion of their total energy needs on renewables - if we’re being honest about the definition of ‘total energy needs’. Like in the camper van scenario, if we include winter heating and transportation? Oh boy. It’s getting better, but if we’re really honest very far from the truth

turtlebits 6mo ago

While I agree with underestimating capacity, the problem only really applies to off grid. For regular homes, it just means less savings.

lazide 6mo ago
It means some other infrastructure (fossil fuels?) needs to take up the slack, and people underestimate actual costs at larger scales. It’s the big issue in Germany for instance - it’s all fun and games until Winter.
- pixl97 6mo ago
  And? Any coal not used in summer is coal not dug up.
- turtlebits 6mo ago
  Which is fine, since you're still reducing your reliance on the grid. However, when you're off grid, underestimating capacity means your SOL and need to buy a generator and burn fuel on-site.
- uecker 6mo ago
  Germany has more wind in winter, so traditionally has more production of renewables in winter months.
  - lazide 6mo ago
    It has dramatically higher thermal heat demands in winter - far higher than is compensated for by that. Even if everyone switched to heat pumps.
    - uecker 6mo ago
      True, but higher demand for heating in winter is not specific to Germany. In the end, Germany will likely need to import energy anyway - just as it does today. But this means this question may not be the most relevant.