Power Efficiency

When we landed in South San Francisco a while back, we had the option at the RV Park we’re staying at to do a monthly rate which was inclusive, or a monthly contract which was $150 less but you paid your own electricity. We took the contract, figuring we had to be using way less than $150/month in electricity – even in winter months when we can’t rely on our solar panels as much. The only other difference was having to fill out more paperwork and sign a lease (which has no commitments of times anyways) and putting up a deposit.

We went ahead and switched our fridge/freezer over to electric (we normally run off propane), and have also been running 2 MacBook Pros, a Mac Mini, a 24″ computer monitor, a 1 TB external hard drive, a wifi router, a small electric space heater (instead of our propane furnace), phone/camera chargers and handful of LED lights. As we’d definitely not be in ‘solar efficiency’ mode anyway, we opted to not be overly conservative with our power consumption to see just what it took to run our whole household at a ‘don’t think about it’ load.

We just got our power bill for a month – 197 KW-hrs is what we used. Which translates to a powerbill of $22.73, about what we spent on dinner last night. Granted, we were out of town for 10 days of the billing period (meaning everything but the fridge was off) – but still, not bad, not bad. Running everything we’d default to, we use less than 10 kw-hrs per day without thinking about it.

Of course, if we were depending on solar alone, we’d have run a major deficit – as on a super sunny day, our 200 watts of solar panels can only generate about 1 kw hour per day (we can store about 2.7 kw hrs in our battery array). Which, we can work with that, especially with supplementing with power collected during towing, being far more conservative and running more stuff off propane. And if we did need to be totally off grid and stationary, our propane generator tops off the batteries nicely.

It’s nice to have the confirmation that our setup is pretty power efficient, even at what we’d consider a ‘full load’.