Electric service - part 1

Today we put in conduit for electrical service to the land.

Jeff at Centerline Construction trenched across the road, from the transformer to the corner of our parcel. They laid down 3 conduits (2 power, 1 telephone), and filled with sand. Apparently there's so much clay that to return the excavated dirt would leave a soft spot. They covered with 3"-minus (a mix of crushed rock that fits through a 3" screen) for a firm, drivable surface.

Here's a broad view from the road, including a steady hail:

The drivable road is about 30' from the edge of the property. After laying the conduit in the trench, they covered with a bit of dirt but didn't fill the trench. Later we'll put a water pipe through here, and then fill the rest of the way.

The trench starts at this transformer. You can see my neighbor's remote meter on the right. We'll have a similar meter, but no transformer.

As the trench passes by the telephone box, it picks up a telephone conduit:

Here's the end of the trench, with the conduit visible. The orange tape marks the dividing line between two parcels. We're developing the one on the right, but the extra 3" conduit is for the one on the left.

Say good-bye to the heavy equipment!

How to build a yurt platform - part 2

We've been digging holes that we marked out before. Here's the template for marking the hole, and an example of the marking:

The plan is that each hole is about 18" x 18" on top, and at least 12" deep. In some areas there's fresh fill dirt, which isn't stable enough, so we will dig deeper where required. Other areas are already cut to firm subsoil, so it's 12" of difficult digging and you're done.

The 12" depth is based on the specified frost depth in this area, as specified by the county's building department. In the previous location the yurt was directly on the ground, with only an inch or two of sod removed, and that worked for 6 years, so this isn't strictly required. But my carpenter friend pointed out the high clay content of the soil and said it would swell with the rains and freezing, so some depth is a good idea.

The ground is glacial till, so it's a well-varied mix. Plenty of clay, silt, gravel, and small boulders. The biggest rock we've pulled out so far was so heavy I had to roll it out of the way. Each spot is different, which is amazing to watch.

We started digging by hand, with a couple shovels and a mattock. I soon added a digging bar, because the mattock couldn't reach the bottom of the holes.

With all 5 of us present, the adults digging and the kids making trouble, we can dig 3 holes on a good day. In one area we hit some roots and it took 2 days to dig 2 holes. At this rate we're talking at least a couple weeks just to dig the holes. After that we have to fill and tamp, set the pier blocks, frame the platform, lay down the flooring, and assemble the yurt. That's a lot of work to do, and we're stuck on digging holes! Still, I like the idea of pointing to the holes and saying "we dug those ourselves!", and some people pay money for the gym while we get to play in the dirt for free-ish.

I thought about hiring someone with a backhoe to dig the holes out for me. That could go really fast, but I think I'd end up with much larger holes than I want.

Yesterday I rented a 2-person gas-powered auger. The biggest bit they had for it was 12" diameter, so the hole isn't as big as we want. But I figured it would get us started. The machine is still a lot of work - it's heavy and it knocks you around as it digs. Rocks less than a couple inches get churned out fine, but over 5" the machine tends to stop digging. Roots slow it down, but it goes. Even the kids helped:

Here Dylan helps us measure a hole:

After digging a 12" round hole with the auger, we still have to shovel the loose dirt in to the wheelbarrow and haul it away, and widen the hole to 18" square. It's way easier, but there's still plenty of work to do. We did this with a couple holes to see how it would go, and then augered out the remaining holes (save 1 because of a big rock) before returning the machine.

The next size up at the rental place is a Toro Dingo with a 24" auger on it. That's about the size of a circle that circumscribes the 18" square we want, so it would be a one-shot deal. The hole is bigger but at least it's a neat, round one. For now we'll dig by hand, though.

Back in the stick house

We spent 3 nights in Coach in the back yard. It was awesome. I loved being close together as a family.

You have you have to keep up with the cleaning, or the space becomes impossible very quickly. It's not hard because the space is small and there's not much stuff.

We moved back in to the house when the graywater tank got full. We could continue if we want to drive to a dump station every few days or so, but I don't really want to do that. We learned a lot from the experience, and have a list of changes we want to make to the RV to make it more comfortable.

Watching music videos in Coach

We've moved in to the RV, at least for tonight. Just in the back yard, but still. Cooked dinner. Brushing teeth next.

The falacy of solar power

That title is a bit inflammatory. It should be "The falacy of solar power on grid-tied homes." Instead of putting solar panels on your roof, here's why you should invest that money elsewhere."

I'm a big green geek, so I've always been drawn to solar power. Now as I am planning to build a new home for my family, I am asking if I should incorporate solar power in to my plans. I have come to the conclusion that putting photovoltaic panels on your roof is almost always a bad idea. Bummer. Read on to see why I think that, and what I think should be done instead.

First, some context. I'm talking about common single-family houses in North America, connected to the electrical grid, where the power company is required to do net metering.

Net metering means that any power you produce in excess of your consumption is sold back to the power company. The nice thing about this program is that you don't have to bother with batteries and charge controllers and transfer switches. That's a lot less equipment, a lot less complexity, a lot less cost. The big items are then the PV panels and an inverter. Any extra power you produce is pushed out in to the grid, and then consumed by someone else in the system. Similarly, any power you consume that you don't produce is pulled from the grid.

With net metering in place, the power you produce isn't really for you to use. Your PV array is just another producer on the electrical grid, while your house is just another consumer. It doesn't matter when you produce, when you consume, or how much. The difference is just settled in dollars.

It doesn't really matter where your PV array is, either. You can move your solar panels + inverter to a location with ideal characteristics - lots of sun. But why limit yourself to just your house roof vs. shed roof vs. a dedicated pole on the ground? Why not your neighbor's house, if it has good sun all day long?

I live in Western Washington, which is known for being overcast a lot of the time. Why not put a solar array up in Eastern washington?

Being close to the equator would improve the output of the panels, so why not put an array in New Mexico?

According to the Department of Energy, Californians pay about twice as much as me for their power. They also have more sun. So why not put up panels in California, sell the power there at $0.15 / Kwh, and use that money to buy my cheap Washington power ($0.08 / Kwh)?

I can also aim for locations that produce their power in ways that pollute. If my power is from water but yours is from coal, better to put my solar panels in your area than in mine.

Producing power at home is quite personal, but producing it at a remote location is different. It would make sense to buy an acre of desert in California and invite people to erect their solar panels there, for a small fee. Or find investors and cover the area with solar, for a return on investment. Bigger systems benefit from economies of scale. Wholesale prices on PV panels and inverters are just the start. Solar/steam/turbines, with a large array of solar-tracking mirrors that superheat water to drive a turbine is pretty attractive, but only at a large scale.

Surely this is better financially than doing it under gray Seattle skies, 1 house at a time, right?

In fact, the power company here (Puget Sound Energy) offerers a "Green Power Program", where I pay a little more for my power (about a penny per Kwh) to do something similar. The money goes to pay for renewable energy production, but you can't really track dollars or Kwh very closely. It's way cheaper than installing a solar array on my roof, though.

So, while photovoltaic panels may be a great technology to invest in, it seems like there are lots of reasons that the roof of your house is not the ideal place to put that equipment.

So, when does solar at home make sense?

First, solar house design. In my climate, that means windows to the south and thermal mass to match, along with plenty of insulation and reducing air leaks.

Second, solar hot water is interesting. No complex electronics or batteries, and it only works close by, so no producing hot water in Arizona to use in Washington. There are plenty of downsides that I won't go in to here.

Third, when off-grid, local solar power can be part of the picture. But this is a lot more expensive and complex than a grid-tied system, and you probably still want a generator for backup when it's not sunny. Again, lots of complexity that I won't go in to here. RV and boat people have this pretty well figured out - go talk to them.

How to build a yurt platform - part 1

Yesterday I started working with a carpenter on the new yurt platform. We spent the day setting up batter boards and string lines to lay out the pier blocks. Here is the result:

There are 30 pier blocks. Each one will sit on a bed of gravel. My next step is to start digging some holes!