I’ve seen a few questions floating around lately about ditching gas and going fully electric in campervans. Induction cooking usually comes up pretty quickly in that conversation.

It sounds great in theory. No gas bottles, no refills, no open flame and often the major consideration no compliance! Just a clean electric setup.

But the question I kept coming back to was pretty simple:

how much solar do you actually need to make that work?

Not in ideal conditions.
Not parked in the sun in the middle of summer.

More like… middle of winter, van parked up, doing normal daily life.

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Starting point

Solar is one of those things where location matters a lot. You see people online talking about setups that work for them, but they might be in completely different conditions.

So I based this on home — New Zealand — and more specifically a winter scenario where you’re only getting about:

~2 hours of usable solar per day

That’s not worst-case survival mode, but it’s realistic enough if you’re actually using the van year-round.

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What I wanted to figure out

I wasn’t trying to design a full system.

Just answer one question:

If I use induction for cooking, how much solar do I need to replace just that energy each day?

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The numbers I ended up with

Induction Cooking	Daily Energy (Wh)	Solar Needed (W)
Light (20 mins)	600	400
Moderate (30 mins)	1000	650
High (1 hour)	2000	1300

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How I got there

Nothing fancy here. Just breaking it down.

First step was estimating how much energy the induction hob uses.

I based it on a 2000W unit, which is about the upper end of what you’d realistically run off a 12V system with a 2000W inverter.

Then I guessed usage:

• Light use
  boiling water, quick meals
  ~20 minutes per day at full power
• Moderate use
  boiling + simple cooking (pasta, etc)
  ~30 minutes per day
• High use
  proper cooking, multiple meals
  up to 1 hour per day

From that, you get daily energy use:

• 2000W × time = Wh per day

That part’s straightforward.

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The part people often miss

The solar side of it is where things get a bit more interesting.

Instead of just guessing panel size, I used solar irradiance (solar hours).

I pulled that from my own calculator here:
https://ianganderton.com/solar-calculator/

That tool is set up to estimate full system output, but in this case I just wanted the solar hours figure that’s also there so I could work backwards.

Once you’ve got:

• daily energy use (Wh)
• solar hours (kWh/m²/day or “sun hours”)

You can estimate panel size pretty easily.

I chucked it into a spreadsheet and worked out how many watts of solar you’d need to replace what you used that day.

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Reality check

This is where it starts to get interesting.

That 1300W of solar for heavier use?

That’s a lot on a van roof.

Even 400–650W is starting to push into “this needs to be thought through properly” territory, especially once you factor in other loads (fridge, lights, charging gear)

And that’s before you even get into battery size.

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What this doesn’t show (but matters)

A couple of things this simple calculation doesn’t capture:

• Inverter losses (you’ll lose ~10–15%)
• Battery charge/discharge inefficiency
• Behaviour changes (you might cook differently once you see the power impact)

But even allowing for those, the overall picture doesn’t change much.

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The takeaway (at least how I see it)

You can run induction cooking off solar.

But in winter, in NZ conditions:

• it’s not a small system
• it’s not a cheap system
• and it’s definitely not “set and forget”

What usually ends up happening is people land somewhere in the middle:

• induction for occasional use
• gas as a backup
• or adjusting cooking habits

Here are some other numbers:

Device	Voltage Type (12V/AC)	Peak Watts	Duty Cycle (%)	Hours Used per Day	Daily Energy (Wh)	Solar Irradiance (kWh/m²/day)	System Efficiency (%)	Solar Watts Needed
12V Fridge (Small)	12V	45	40	24	432	2	75	288
12V Fridge (Large)	12V	70	50	24	840	2	75	560
Phone Charging	12V	10	100	2	20	2	75	13
Laptop	AC	45	100	2	90	2	75	60
Maxxair Fan (Low)	12V	10	100	8	80	2	75	53
Maxxair Fan (High)	12V	40	100	4	160	2	75	107
Induction cooking (light)	AC	2000	100	0.3	600	2	76	395
Induction cooking (moderate)	AC	2000	100	0.5	1000	2	77	649
Induction cooking (high)	AC	2000	100	1	2000	2	78	1282
Air Fryer	AC	1700	60	0.5	510	2	78	327

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If you want to run your own numbers

Here is a DROPBOX LINK to the spreadsheet I used so you can plug in your own setup and see what happens.

That’s probably the most useful way to approach it — everyone’s usage is slightly different, and small changes add up quickly.

They say a picture tells a thousand words. Well this one doesn’t tell you anything about the past 2 days!! Behind the picture of a very pretty rainbow hides stories of the longest day I’ve ever had on a bike and multiple near death experiences in 100km that I thought was just going to be a nip down the hill. 

It started benignly enough, an early(ish) start from Hawden Shelter campsite just below Authurs Pass. I was heading for Loch Katrine campsite via Lees Valley and lots of other tracks on Josh Martin’s (Adventure Guide) Smoking Dragon “Adventure”

By 1pm I was not far from heading up the hill via Lake Sumner Road and going to be at the campsite pretty early. 

I’d had it in my radar to do Adventure Guides Banks Peninsular adventure. On let’s do it 👍

(Ed: hmmmm perhaps it’s all Josh’s fault 🤔)

What was a 380km planned day became a 707km day (lots and lots of gravel) with about 14 hrs riding time and a huge amount of ground covered. 

This wasn’t wandering and stopping to look at the view adv riding. From midday onwards it was missioning, it was all about getting the job done and if possible before the light failed. 

I often ask myself “what is adventure?”, it’s something that I find intriguing. Suffice to say I think it’s complicated but in essence it’s about uncertain outcomes. That might be trying something that might not succeed or going places I haven’t been before. Yesterday ticked my adventure boxes and a learnt a lot from it. It’s good to know I can do I ride that involves 14 hrs of getting the job done 🤓

So it was a very tired Ian  that arrived at Lake Taylor campsite in the last of the daylight, pitched his tent at and crawled into my sleeping bag last night 

Sleep 😴 

Not much. The wind picked up and up and up

Tired Ian didn’t get much sleep as the +100km/h wind roared like a jet engine through the big trees lining the lake/campsite boarder shaking my new tent to its limits. 

Daylight arrived and the wind didn’t change. The wind was sooo wild it was ripping the water surface off the lake in clouds of spray

Wind was forecast to continue but it was also forecast to start hosing down with 40mm of rain 🤔

Fortunately Taylor’s lake has a cooking shelter more akin to a hut than a shelter. I was looking at spending the day there riding out the storm. I figured I had a book plus plenty of food and coffee

But

Nightmare! My new Jetboil has shat itself. I couldn’t get it to fire up initially and then when I did it was an unregulated ball of death flame 🔥 😩

Faaark. 

Place to hide from the weather – tick ✅ 

E-reader loaded with books – tick ✅ 

Hot drinks (tea or coffee I don’t care) – nope 👎 

Food – nope 👎(I’ve only got dehydrated meals with me)

Faaark

At this point I had a really cool encounter with another resident of the wind blown campsite. A fellow Brit who had a working stove and a mokka coffee pot. Plenty of coffee and chat later and the weather looked like it was improving. 

The wind was no longer ripping the surface off the lake but the rain radar was showing there was plenty to come. Was this the time to duck through the gap and head to civilisation 🤔

So I did, I ducked out and made a beeline for Hanmer Speings Top 10. A world of hot showers and a working kettle. 

but

The ride down Lake Sumner Road was fine but I picked up a significant tail wind as I hit the plain. In the future I’ll know the problem this was going to cause

It turned out this tailwind was still gusting +100km/h on the Cantubury plains and once onto the main road it was a brutal side wind doing all that it could to push me into the oncoming traffic 😧 

The next 60km were probably some of the most terrifying I’ve done. One moment I’d be coping ok, the next I was being pushed hard to the right by and irresistible force with tonnes of immediate death steel racing towards me. 

I should have stopped in Culverden. The town was super busy with lots of other people stopped but rightly or wrongly I had my eye on the prize and so I pushed on

After Culverden the wind exposure ramped up. What I didn’t think could get worse did. It culminated just as I was about to exit the plains and head into the foothills. I think a constriction was accelerating already brutal winds to the point where it had blown out a caravans windows. There was glass everywhere and the police had stopped traffic.

Once stopped it was horrendous! I was really struggling to keep the bike upright. I pulled onto the side and even on the side stand it was impossible. I had a shouting conversation with the cop who was hiding behind his patrol  car. He was asking if I was alright, I was saying NO!

I spend somewhere around 30mins there hanging onto the bike in what felt like a full jet blast of these ferociously hot winds. I haven’t mentioned yet how hot it was. I’d kept my waterproof on from the escape from Lake Taylor because it’s very HiVis and I needed any help I could get in preventing my impending death on the road. As a result my elbows were wet from the gathering sweat 😰 cause by the 100km/h hot winds

After 30 minutes of literally hanging hoping something would change I decided I needed to try changing something and at the very least finding somewhere with some shelter. 

Getting going was hard and scary but as I got going again it felt safer. Once I got to the turn off to Hamner the road got some shelter. 

The relief of arriving at the campsite was significant. I was finally safe and could stop. 

There was both a physical and mental toll from riding in the wind. I was so tired from both. Power is off in Hanmer so a shower hasn’t been possible yet. The wind is so drying I could feel a crusty ring of dried snot around my nostrils. I’m really looking forward to the luxury of a shower

Only one pub in Hanmer has a back up generator but I found a table and have availed myself of its facilities 🍺 

So what’s adventure? 

Would it have been adventure to not do dumb shit like adding a 240km extra loop to and already 380km planned ride 🤔

Would it have been more sensible to stay out at Lake Taylor and suck up the lack of coffee and ride out the storm 🤔 rather than putting myself through all those near death experiences. Where does hindsight sit in this?

I’ve definitely learnt some shit about myself and riding decisions I might make in the future. In simple terms:

• I can do 14hr of riding days if needed. They are tough but I can do them
• 100km/h winds are fucking dangerous for motorcyclists. I know “no shit Sherlock!!” But sometimes you just gotta learn the hard way
• Beer tastes sooooo guuuuuuud when it’s been really earned 🫡

AirShare is the hub for recreational and commercial drone operators in New Zealand. The map in their app includes important information for drone pilots but its difficult to see easily so I’m putting both text and an image here so I can access it easily.

• ATC Restrictions – Flights inside black or red lines may have additional restrictions. Air Traffic Control will advise.
• Low Flying Zones – UAVs are not permitted in any Low Flying Zones which are coloured orange.
• Military Operating Areas – Permission from the administering authority is required to fly in these green zones.
• Aerodromes – The blue circle areas indicate a 4km radius around aerodromes
• Other Authorities’ Areas – This area requires you to gain approval before you fly from the administering authority or landowner
• No Fly Zones – These areas are where you are unlikely to receive approval to fly from the administering authority or landowner
• Danger Areas – These areas are where an activity within is a potential danger to aircraft flying over the area
• Notice to Air Missions – A NOTAM contains important information that could affect the safe operation of your flight

In this post I aim to collate useful cassette toilet options information for NZ based van builders to help then meet the fixed toilet requirement in the new 2023 Self-contained Motor Vehicles Legislation Act.

Information on the 2023 changes to the Freedom Camping Act can be found at https://www.mbie.govt.nz/dmsdocument/26796-local-government-guidance-pdf#:~:text=The%20Act%20enables%20local%20authorities,apply%20to%20that%20particular%20area.

The purpose of this document is to provide guidance on the key changes implemented by the Self-contained Motor Vehicles Legislation Act 2023 (the Act) which will impact local authorities.

Key for NZ Campervan owners/builders is the new Self Contained requirement for a fixed toilet.

Edit 12/07/2024 – The details of exactly what this means can now be found in this document https://www.pgdb.co.nz/media/cqubmqa3/vehicle-inspection-guidance-v10.pdf

is permanently fixed to the vehicle with the base of the toilet rigidly mounted in position and
does not require removal in order to empty human waste;

Consult the linked document for a full list of requirements.

NB There is a requirement for the cassette or tank to be vented to the outside. This requirement is currently under review

Fixed toilet options:

CTS4110 – swivel, ceramic inlay, 12v electric flush, pressure supply water
Dimensions are D530mm H672mm W382mm. As only the toilet seat swivels, these dimensions do not significantly change when rotated 90 degrees.

Dometic Saneo CS – swivel, ceramic inlay, 12v electric flush, pressure supply water

D602mm H680mm W377mm. As per diagram below, depth is 549mm with bowl at 90 degrees (assume width increases by 50mm also)

Thetford C223-CS – swivel, plastic bowl, 12v electric flush, pressure supply water

H534 x W414 x D580 mm. As per diagram below, depth is 556mm with bowl at 90 degrees, width increases to 427mm

Thetford C224-CW – swivel, plastic bowl, hand pump flush, on board flush tank

H731 x W414 x D580 mm. Same platform and swivel measurements as C223 above, but taller due to onboard flush tank.  

Thetford C263 – swivel, ceramic inlay, 12v electric flush, pressure supply water
H750 x W417 x D600mm. As per diagram below, depth is 541mm with bowl at 90 degrees, width increases to 464mm

Thetford C402 – Bench, plastic bowl, 12v electric flush, on board flush tank
H512 x W670 x D400 mm. Bench type, comes in left and right hand models – choose the side that the cassette will be removed from.

CHH 3924 – non-swivel, hand pump flush, on board flush tank
SCNZ have stock of the below pictured toilets coming in October. These have onboard flush water tanks and piston pump flush so do not require pressurised water supply or 12V. Price will be approx $700. Measurements are D530xW395xH480mm.

NB – A swivel option is planned to be available at some point in the future but it wont be the near future.