solar power

Snowstorm!

Several days without power, but with snowy beauty.

A large snowstorm passed through New Hampshire on Friday and Saturday. At our house, snow fell for about 26 hours. It was warm (33º), so the snow was wet and heavy, accumulating to a depth of 8″ … but I just know that higher elevations would have seen fluffier snow that got much deeper. Can’t wait for a chance to get out and hike some mountains!

Unfortunately, the weight of all this snow caused many trees and branches to fall, blocking roads and knocking out power and Internet across the region. We are fortunate to have battery backup – which lasted for about 17 hours, fed in part by our solar tracker soaking up the post-storm sunshine. In turn, the batteries can be refilled by a propane generator. (The relationship between the two is complicated and buggy, but that’s another story.)

I took the opportunity to ramble around the backyard – local authorities asked everyone to stay off the roads unless necessary – and try to improve my ability to find interesting compositions and to expose properly for snow. Check out the gallery; at the end is a bonus: bald eagles spotted high in the trees during my afternoon walk, including a short video of two eagles taking off to fly across the river and greet a third bald eagle in the trees over there. (Apologies for the low-res iPhone photo and video… it’s all I had with me.)

P.S. Grid power is back! After about 39 hours.

Solstice power

Sunny days!

As I noted, yesterday (June 21) was the summer solstice, and I was hopeful we might have a banner day for solar power at home. Unfortunately, it was a mostly cloudy day and we only generated 28kWh.

The day before (June 20), however, was fantastic – over 56 kWh!

Summer solstice

Longest day of the year?

Today is the summer solstice (in the northern hemisphere). More precisely, the solstice occurred at 5:15am here in the Eastern timezone. The summer solstice is the moment at which the sun has ‘traveled’ to its northernmost latitude, in its annual cycle of apparent movement to the north in summer and to the south in winter. (It’s a great day for those of us with solar panels, because it means we’re getting hours of sunlight!) Read on.

Equinox

Equal day and night.

Today (22 September) is the fall equinox – when we have equal amounts of the day with sun and no sun. The length of the day is changing fast – indeed, faster than any other time of the year except spring equinox – and it is really noticeable every day. Today was rather cloudy, not a great day for solar power:

Spring equinox

Spring is here in the valley.

Today is the vernal equinox – the spring equinox – when the length of day and night are equal (equi = equal, nox = night). Actually, “They are not exactly equal, … due to the angular size of the Sun, atmospheric refraction, and the rapidly changing duration of the length of day that occurs at most latitudes around the equinoxes” [Wikipedia]. Here in New Hampshire, Sunrise was at 6:51am, Sunset at 7:01pm.

For those who welcome the arrival of spring, today is when we are adding more minutes of sun per day than at any other time. We’re on the steep part of the curve! This is great news for our solar tracker, which put in a banner effort today under nearly clear skies, with a total production of 45.57kWh:

Technically, the equinox is “the instant of time when the plane of Earth’s equator passes through the geometric center of the Sun’s disk” [Wikipedia]. This year, that occurred at 0937 UTC, or 5:37am here in Lyme, which happens to be about when I got up this morning.

Interestingly, it has long been noted this is the “day when the Sun rises due east and sets due west, and indeed this happens on the day closest to the astronomically defined event.” [Wikipedia again].

On cue, the Connecticut River decided it is also ice-out day – the day the winter’s ice breaks up and the river begins to visibly flow. I’m pleased to see open water, because it means that bald eagle might be seen more often in our neighborhood once again, now that it has an opportunity to fish.

ice-out on the Connecticut River, in front of our house

The forecast shows nothing but clear skies, warm days (50-60º) and cool nights (20-30º). Great weather for sugaring! More on that to come…

Solar flat

Even on a windy day, we can still generate power.

It was a wild and windy night, as a cold front blew away yesterday’s warm temperatures. Our solar tracker is designed to protect itself by going flat when there are gusty or strong winds, and that’s how I found it this morning.

Solar tracker goes flat in windy conditions.

You can see the anemometer at the far-right corner, which is on a gimble so it can measure horizontal wind speed even as the tracker tilts.

That picture was taken about two hours ago. It’s now quite sunny, and still windy; the tracker is still flat (and thus not pointed at the sun), but still generating enough power to serve the house, charge the battery, and feed the grid:

Solar complete

Solar and battery and generator.

Finally, more than six months after we received the initial proposal from a local solar-power company (Solaflect), we have a complete system installed: last week, they completed the installation of a battery back-up solution from a German company called Sonnen. Our house can now be supplied by solar power, grid power, battery power, or propane-generator power, depending on the situation. Although I won’t dig into all the details, it’s pretty cool, so read on…

diagram of power flowing — A screenshot from the Sonnen battery portal showing power flowing from the solar tracker into the house (supporting its consumption) and into the battery (keeping it charged) and into the grid (selling power back to the electric company). The actual graphic is animated, showing power ‘flowing’ from the top to the other three destinations.

Now I can charge my car with the sun.

One of our other major summer projects was the installation of a solar-panel tracker from Solaflect Energy – a local company from Norwich, VT that designs, builds, and installs its custom solar-tracker system in households and small businesses around the Upper Valley. We’ve been interested in going solar for years, and finally decided to take the plunge. As an added bonus, it (indirectly) serves to fuel my new Tesla. Read on!