Your Questions About Solar Energy Panels

Michael answers:

Vs. Coming off the grid?

Solar panels produce lower voltage DC. Household components want AC at a higher voltage (110VAC at 60Hz in the US)

To be useful, generally you have an “Inverter” which increases the voltage and alternates it. You also probably have a pile of storage batteries since otherwise you’ll have no power during the night or bad weather.

These days, people have hybrid systems, getting power both off the grid and from a local power source (windmills, solar power). Some don’t bother with storage on the idea that they put power INTO the grid when they are generating more than they need locally, and take it out of the grid when they aren’t producing enough. They use their local power company as a very large (cheap) battery.

You can only do this if your local power company will pay you for power you generate – but many states in the US require power companies to do that.

However, if you are cut off from the grid, you obviously can’t do that.

You can, of course, NOT use standard household components, but rather use low voltage DC components (like what people use on small boats). They exist, but they are more expensive. However, then you don’t require the inverter.

As soon as you want to use a standard voltage component, however, you end up getting an inverter. Its too bad because he process of changing voltages is inefficient. You lose a lot of power in the process.

Michael answers:

Solar panels really can’t compete with fossil fuels of any kind.

They’re great for low power consumption applications, but I doubt we’ll ever see solar powered steel refineries or heavy manufacturing plants.

A solar panel that produces 175 watts is about 62″ x 33″ (5 feet by almost 3 feet). 175 watts is enough to power a couple light bulbs; you’d certainly never cook anything on it.

On the other hand consider how much heat and light is produced by a small natural gas fireplace or stove burner. It would take a lot of those 5 foot long solar panels to equal that.

Michael answers:

Probably very little, it’s at such a high latitude. Anchorage gets way less than half the annual sunlight that LA does, for example:

http://www.solarpanelsplus.com/solar-insolation-levels/

The trans-Alaska pipeline is about 800 miles long. Let’s assume you could fit 1.5 metres wide of panels all along the pipeline, and the efficiency of these panels is 10% (First Solar CdTe are the cheapest, and 8-10% efficient modules. Silicon is more expensive but generally higher efficiency).

The surface area is 1.9 million square metres, which will receive an average of 4 million kWh/day at Anchorage levels of sunlight, or make 0.4 million kWh/day of electricity (ofc, lots more in summer than in winter!)

0.4 million kWh is the energy content of about 2,300 barrels of oil.

However, you must remember that here you’ve accounted for the efficiency of the solar panels but not the efficiency of the oil. If you burn the oil in a car engine, you’ll average 12-20% efficiency in general (and that’s not accounting for the energy needed to dig up, process & distribute the oil or make the solar panels). Assuming you’re using the oil to drive, it’s equivalent to about 10,000 barrels of oil per day, or 3.65m a year.

Michael answers:

Wolfe island off Kingston in Lake Ontario

Michael answers:

The more sunlight that gets in the more power out of a solar panel. Less ozone more sunshine.