We are seeing a growing trend of customers who are asking about going off-grid with solar and battery backup for their home in the city. Until just a few years ago when the decay of our countries infrastructure and dysfunctional Congress, they would have been a small fraction of the off-grid solar community.
The short answer is, yes, absolutely you can go off-grid in the city. Fact is it might be a smart move right now considering the broken economy. The only question is how much money…which is the “realistically” part of things…because technically it is totally easy. When you buy solar panels you are paying up front for 25 – 40 years of energy generation. Imagine paying all the electricity bills from the past year tomorrow times 40, that might be $40,000 to $80,000 (and that is without taking into account that the price of grid electricity will keep going up so it’ll likely be 100,000 to $200,000 the way oil prices are going).
By reviewing your current electricity bills for the past few years you can determine how much off-grid electricity backed up by solar you need at various times of the year. If you are disconnecting from the grid then you need to be able to generate enough for your peak days. Off the grid the only way to do that is by combining solar with batteries and/or a generator. Lessening your load with efficient appliances makes things less expensive in the long run…more on that in a bit.
If you just want to do it without consideration for cost then you could probably add a $200,000 solar pv system with batteries to get off the grid. The solar panels will last 40 years but the batteries would have to be replaced every 10 to 20 years depending on what type they are. Not that our current economic system tells us this, but this is a pretty good deal if you could factor in the health cost savings and environmental benefits of eliminating pollution. Half the cost in this scenario is batteries since it is off the grid. Also the solar system has to be big to handle peak days and low sun days. We’ll likely spend this amount and more on the grid over 40 years, so it is just the paying for it all up front that is the only difficult part.
The best way to get off-grid or emergency solar economically:
1. Spend less on the solar system by getting the very most efficient appliances you can. Switch lights to LED. Get the smallest fridge you can live with and find the one with the lowest Energuide rating for energy consumption. That goes for the dishwasher, washing machine and computer. Also make sure you don’t have any “phantom loads”, like televisions that use power even when they are “turned off”. Find every single phantom load and prevent it by using a power bar that you can use to truly switch it off.
2. If the water heater is electric invest in a solar water heater…$3000-6000, pays for itself in 6-8 years but is critical as a part of getting off the grid.
3. Assuming you have equity in your home get a home equity line of credit to invest in your solar panels system. Work with a solar installer that specializes in off-grid solar to size a solar system for your south facing roof and as an awning above the south side windows. Ideally you can fit 5,000 – 10,0000 kw of solar which would cost between $40,000 and $100,000 fully installed. Now, since you are getting a home equity line of credit to do it, plan to install in spring. That way with your 20 year contract that pays 80 cents/kwh you’ll be getting monthly payments that more than cover the borrowing costs…so for instance I got $1000 for July with my 6 kw solar system which more than covers my monthly loan payment of $400. Doing it this way actually pays you a profit for adding those solar panels, but you do need to remain on the grid to do this, and you’ll still pay for electricity you consume, although you may have that covered by the profit from your solar system….depending on how well you do with step 1 using less. You should have your loan paid off in less than ten years which is great, as you’ll be earning pure profit for the next ten years…which will more than pay the electricity bills.
4. After 20 years you add batteries, which will be far advanced from what we have today and will last at least 20 years which is likely the lifespan remaining in your solar panels, and disconnect from the grid. The profit for the last ten years of solar on the Microfit will more than pay for these batteries.
This is what I am doing. We put a 6 kw solar system on last summer. In the first month I got $600…which covered the loan payment on our $45,000 system. This July we got $1000 for our solar generation. Of course in January and February the payment goes down to $350 or so, which is why it is important to install in spring, so you’ll have enough saved to cover payments in the low sun months. Off-grid solar makes sense for a growing number of people living in the city.
Source the Village Solar