This guide covers what drives the cost of a standalone off-grid system in coastal BC and how to compare quotes. For the separate question of whether to connect to the grid instead, see off-grid vs a BC Hydro line extension. For grid-tied pricing, see solar panel cost in Vancouver.
There is no honest single price for an off-grid system, and anyone who gives you one over the phone is quoting a system they have not designed. What we can do — and what this guide does — is show you exactly what the money goes on, which decisions move the number most, and how to compare two quotes that look nothing alike.
Why off-grid costs more than grid-tied of the same array size
A grid-tied system is an array, an inverter and some wiring. The grid provides storage, backup and the ability to cover a bad week for free. Off-grid you have to buy all three of those functions as hardware, and that is where the difference sits.
- Storage. A grid-tied home may have no battery at all. An off-grid property cannot function without one, and the bank is sized for days of autonomy rather than an evening. It is usually the single largest line item.
- A larger array. Off-grid arrays are sized against the worst month rather than the annual average, which means deliberately oversizing relative to what a grid-tied system would need. See sizing for a BC winter.
- The generator. Auto-start generator, its housing, fuel storage and the wiring to integrate it with the inverter/charger.
- A more capable inverter. An off-grid hybrid inverter/charger has to form the grid itself, handle surge loads, manage charging and control the generator. That is more equipment than a simple grid-tie string inverter.
- Site work. Remote properties frequently need ground mounts, trenching, equipment buildings and access work that a suburban roof install never encounters.
The seven things that actually move the number
1. Your December loads
This is the dominant variable, and it is set by you rather than by the site. A cabin running lights, a fridge, a pump and some electronics is a fundamentally different system from a house running electric heat and electric hot water through a coastal winter. Taking heat and hot water off the electrical system with wood or propane is the single largest cost lever available on most off-grid projects.
2. Days of autonomy
How long the property must run with no meaningful sun. Every additional day is more battery, and battery is the expensive part. Fewer days means a smaller bank and more generator hours, which trades capital cost for fuel and servicing.
3. Full-time or seasonal
A property closed from November to March skips the hardest weeks of the year entirely, and the system gets dramatically cheaper because it is no longer designed against a coastal December. Be honest about this at design time — retrofitting a seasonal system into a full-time one costs far more than building for full-time at the outset.
4. Battery chemistry and usable capacity
Lead-acid looks cheaper per nameplate kilowatt-hour and is more expensive over the life of the system, because you can use less of its capacity and it lasts fewer cycles. Compare quotes on usable capacity and expected service life, not on the headline number.
5. Array mounting
Roof mounting is generally cheapest where the roof is suitable. Ground mounts cost more in foundations and trenching but often produce better on a rural property, because you can set ideal tilt and orientation clear of the tree line. On many off-grid sites the ground mount is the better system even though it is the more expensive install.
6. Access and remoteness
This one is invisible in equipment lists and very visible in the final price. Barge or ferry freight, limited road access, long walks from the parking spot to the building site, and crew travel and accommodation all add real cost. Two identical systems can differ substantially on logistics alone.
7. What you already have
An existing generator, an equipment building, a suitable roof or an existing trench can all reduce the number. So can building the electrical rough-in during construction rather than retrofitting it afterwards.
The costs that arrive after the install
An off-grid system has a lifetime cost, not just a purchase price, and a quote that ignores this is not comparable to one that does not.
- Generator fuel. Concentrated in the winter months, and dependent on how the system was sized. A smaller bank means more running hours.
- Generator servicing. On hours rather than dates, and the hours accumulate in the season when getting a technician to a remote property is hardest.
- Battery replacement. The bank has a defined service life shorter than the panels. Expect to replace it once within a typical period of ownership, and design physical access so that is a straightforward job.
- Inverter replacement. Likely once over the life of the array.
Panels are the reliable part — they degrade slowly and predictably and generally carry long performance warranties. It is the electronics and the storage that have a service life.
Tax: what is exempt and what is not
This materially affects an off-grid quote, and it is regularly got wrong. Under Bulletin PST 203, solar photovoltaic panels, wiring, controllers and the devices that convert DC to AC are exempt from provincial sales tax when obtained as part of a system that includes panels.
Batteries are explicitly excluded. The bulletin states they “are considered generic goods and do not qualify for the exemption, even if they are obtained for the operation of ocean, wind, solar and micro-hydro power generating systems.” On an off-grid build, where the bank is often the biggest line, this is a real number — and a quote showing the whole system as tax-free is wrong. Detail in off-grid rebates and taxes in BC.
There is also no BC Hydro rebate to offset any of this. Those rebates require a BC Hydro residential account and a connection to the distribution system, which an off-grid property by definition does not have.
How to compare two off-grid quotes
Off-grid quotes are far harder to compare than grid-tied ones because the systems differ in more dimensions. These questions normalise them.
- What usable battery capacity is quoted, and at what depth of discharge is that figure calculated?
- How many days of autonomy does that represent against my actual load list?
- How many generator hours does the design expect in a normal winter, and in a bad one?
- Is the generator auto-start, and is that integration included?
- What is the inverter surge rating, and does it cover my well pump starting while something else runs?
- Which line items are being treated as PST-exempt, and is the battery quoted with tax included?
- What is included for freight, access and crew travel to this specific site?
- What monitoring is included, and can I see state of charge remotely?
- What are the warranties, separately, on panels, inverter, battery and workmanship?
A quote that answers all nine crisply is from someone who has built off-grid in coastal BC. A quote that answers none of them is a price for equipment, not for a working system.
Why we will not publish a price range
Because the honest range spans a multiple, not a percentage, and a headline figure would mislead more people than it helped. The difference between a seasonal cabin with propane heat and a full-time home with electric everything is not a variation on one price — they are different projects.
What we will do is model your actual loads and site and give you a fixed figure with the assumptions visible, so you can see which decisions are driving it and change them.
Frequently asked questions
Is off-grid cheaper than connecting to BC Hydro?
Sometimes, and it depends almost entirely on the extension estimate for your address. BC Hydro contributes up to $2,690 per residential dwelling toward an extension and you pay the balance, which on a remote property can be substantial. Off-grid carries costs a connection does not — generator fuel, servicing and an eventual battery replacement — while a connection carries a bill for as long as you own the property and makes you eligible for rebates. Get the extension estimate first; it is the number the decision turns on.
What is the most expensive part of an off-grid system?
Usually the battery bank, and it is also the part most affected by your own choices. Days of autonomy and winter loads drive its size directly, which is why taking heat and hot water off the electrical system changes the total cost so much.
Can I build it in stages?
Often yes, and on a new build it is common to install the array and a smaller bank first, then expand. It works best when planned from the start — leaving electrical capacity, physical space and the right inverter to accept expansion. Mixing significantly different battery vintages in one bank is poor practice, so staged growth usually means a second properly integrated bank rather than adding modules to an ageing one.
Do off-grid systems qualify for any rebate in BC?
Not from BC Hydro — those rebates require a BC Hydro account and a grid connection. The provincial PST exemption does apply to panels, wiring, controllers and inverters, but not to batteries. If the property is a business asset, federal clean-technology tax measures are a separate question worth raising with your accountant.
How long does an off-grid system last?
Panels are the long-lived component and typically retain the large majority of their output after two and a half decades. The inverter will likely need replacing once over that period, and the battery bank has a shorter defined service life — expect to replace it once within a typical period of ownership. Designing physical access for that replacement at the outset is cheap; retrofitting it is not.
Sources
- Government of B.C., Bulletin PST 203 — Energy Conservation (revised September 2022).
- BC Hydro, Rebates for solar panels and battery storage — account and self-generation eligibility.
- BC Hydro, Distribution Extension Policy changes — contribution allowances.
Sizing up the alternative before you have a quote
Because this is nearly always a comparison, it helps to know roughly what the other side costs before either number arrives.
BC Hydro does not publish a per-metre extension rate. It does publish enough in its rate-design material to place yourself: it has noted that a 300 metre threshold “would include approximately 90% of historical connections,” and its April 2024 workshop shows illustrative connection examples of $25,254 for a single detached house and $35,349 for a four-unit multiplex — against a current BC Hydro contribution of $2,690 per dwelling.
Read together, the shape of the decision appears. A property a few hundred metres from a line sits in the ordinary case, and connecting usually wins: you keep BC Hydro rebate eligibility and you avoid buying storage, a generator and a deliberately oversized array. A property well beyond that sits in the tail, where the extension can approach or exceed the cost of a complete standalone system you own outright and that carries no bill for as long as you hold the property.
Full detail, including what the deposit tiers reveal and a caution about conflicting figures on BC Hydro’s own site, is in off-grid vs a BC Hydro line extension.