Anyone else finding their van solar setup genuinely struggling to keep up with EV charging on the road?

Running a 400W roof array (2x 200W Renogy panels) into a Victron MPPT 100/30, feeding a 200Ah Fogstar Drift LiFePO4. Works a treat for the usual stuff — lighting, 12V fridge, laptop. No complaints there.

Problem is I've started trying to top up my EV overnight via a portable EVSE plugged into a 1000W inverter. Even a slow trickle charge at 6A is absolutely hammering the battery. Woke up one morning at 38% SOC which made me nervous even with LiFePO4 chemistry.

Is anyone actually making van-based EV charging work without shore power or a massive battery bank? Feels like the maths just doesn't stack up unless you're running 600W+ of panels minimum. Curious what setups people are actually using rather than what looks good on paper.

@LuckySkipper the maths is pretty brutal here — 400W peak realistically gives you maybe 1.5–2kWh on a decent UK summer day, and EV charging eats that for breakfast even at slow rates.

What I've found with my motorhome setup (similar spec actually, 400W into a Victron SmartSolar 100/30) is that solar alone simply isn't viable for meaningful EV top-ups. You're better off thinking of it as offsetting your driving consumption rather than replacing a hook-up session.

A few practical options worth considering:

• DC-DC charger pulling from the vehicle alternator whilst driving
• Prioritise solar for your 12V loads exclusively, hook-up for the EV
• Look at whether a B2B charger like Victron's Orion-Tr Smart makes sense for your setup

Your 200Ah Fogstar Drift is excellent kit but it's a relatively modest buffer for EV demands. Realistic expectations will save you a lot of frustration.

@LuckySkipper what EV are you actually trying to charge from it? That's the missing piece here. Even a small 3.7kWh "buffer" battery like on some older Renaults needs more than your entire daily harvest just to move the needle meaningfully.

@SimonKelly's maths is spot on, but the timing matters too — if you're parked up and generating all day before plugging the EV in at dusk, you're at least maximising what you've got. Trying to charge simultaneously is a losing battle.

Realistically though, 400W just isn't the tool for EV topping-up. You'd want to be looking at dedicated charging stops or accepting it'll only add single-digit miles per day. Some folks use the van solar purely to offset home charging costs rather than expecting genuine road capability. What's your actual use case — emergency top-ups or regular daily range extension?

@LuckySkipper I run a similarly-sized setup in my shepherd's hut for emergency backup, and the penny dropped for me when I realised I was essentially asking a garden hose to fill a swimming pool.

The maths everyone's dancing around: your 200Ah Fogstar holds ~2.5kWh usable. Most EVs won't even initiate a meaningful charge session below 1.4kW sustained input. Your solar isn't a charger — it's a trickle.

What's your actual use case though? If you're parked up for 3–4 days between drives, a decent DC-DC charger into a larger buffer bank might just about work for range anxiety top-ups. But "charging an EV from van solar on the road" is genuinely one of those ideas that sounds brilliant until someone does the arithmetic on a napkin.

What inverter are you running between the Fogstar and the car's onboard charger?

@LuckySkipper mate, asking 400W of solar to charge an EV is like bringing a watering can to fill a swimming pool — technically it works, eventually, if you're not in a hurry and don't mind weeping quietly.

My boat setup taught me the hard way that LiFePO4 capacity and solar input are two completely separate battles — you can have a gorgeous 200Ah Fogstar and still be taking from it faster than the panels replenish.

Realistically you're looking at shore power or a DC-DC from the vehicle alternator while driving as your actual EV top-up strategy — the solar's job is just maintaining the leisure bank, not performing miracles.

Victron's VRM app will show you exactly how badly the maths is hurting you, which is equal parts useful and depressing.

@LuckySkipper the maths is pretty brutal when you work it through. Even a cracking 6-hour solar day gives you maybe 2kWh from that array after losses — that's roughly 6-8 miles of EV range added. Hardly worth the hassle of setting up a charge session.

What's worked better for me is flipping the thinking entirely — use the van solar to displace other consumption (fridge, lighting, devices) while you top the EV at services or a destination charger. Your battery stays healthier and you're not sitting watching 1.2 amps trickle into something that wants 7kW minimum.

@BirchDaz makes a fair point though — the EV model matters enormously for 12V trickle options. Some have auxiliary ports that behave more sensibly than others. What are you actually driving alongside the van?

@SussexBoater 😄 that watering can analogy is brilliant and pretty much sums it up.

My situation's slightly different — I've got a garden office setup rather than a van — but the principle's the same when I tried using mine as emergency backup for higher-draw devices. The honest answer is solar just isn't the right tool for bulk energy replenishment, it's brilliant for maintenance and offsetting.

For EV charging specifically, you'd really want to be looking at shore power or a proper DC-DC solution from the vehicle's alternator while driving. The Victron Orion-Tr Smart range handles that side of things well if you're doing serious mileage.

Your Fogstar/Renogy combo is solid kit — don't ask it to do something it was never designed for and it'll serve you well for years.