We’ve talked about Bullfrog Power here before, but we have only just today signed up with them. (Ooops.)

We just had that down as one of those small tasks we’d take care of once the house was built which was going to get underway any day now for the whole year. But since we’re now officially on house-building-hiatus, our plans have been getting shifted around.

Another task we put off last year was replacing our awful, scary fridge because we thought “We don’t want to have to move a brand new fridge into storage, when we could just dispose of this one when construction starts, and buy a new one when we’re ready to move in.”

This fridge was so old it proudly boasted an Energuide rating of 1742kWh/year. But that was when it was new. We had put a UPM EM-100 usage meter on it (~$25 @ Canadian Tire) and found it was actually running at a rate of almost 2400kWh/year. You would think the fact that our old fridge used almost $250/year in electricity would be incentive enough to get rid of it right away, but for some reason waiting just a couple more months seemed like a good idea at the time (and the next time, and the next time).

Our new fridge (18.2 cu.ft.) is a fantabulous Whirlpool ET8FTEXRQ (note to marketing: not the catchiest name) and uses just $39/year or 412kWh of electricity. So, our electricity bill just came down by about 40%! We selected this particular fridge because it is the close cousin of the 21 cu.ft. ET1FTEXRQ which is currently the top rated fridge at Consumer Reports.

A call to Whirlpool’s “Customer Experience Centre” (yes, it’s an awful name but the staff there were top notch) revealed that, mechanically, the ET1 and ET8 are the same fridge, just different sizes. In case you go looking for it yourself, you should know that the ET8FTEXRQ has been replaced by the ET8FTEXSQ. I did not call them to ask what the difference was.

We made the semi-mistake of buying it from Lastman’s Bad Boy because they had a great price on the fridge we wanted, but I’ll blog about that experience another day.

For our initial meetings with contractors Joanne & Alex had put together a list of materials we will likely use in the home’s construction. Here they are:

Below Grade Enclosure

• Foundation Wall Assembly
• Clean, Free-draining backfill
• 2″ Roxul DrainBoard Foundation Insulation
• Damp-proofing on cement parging
• 10″ Durisol ICF
• 3/4″ strapping
• 1/2″ DensArmor Plus

• Basement Floor Slab Assembly
• 4″ Compacted Gravel Base
• 2″ EPS Insulation
• 6mil Polyethylene Sheet
• 4″ Concrete Floor Slab

Above Grade Enclosure

• Wall Assembley (R40)
• Fibre Cement Board Cladding
• 3/8″ Strapping
• 4″ Polyisocyanurate Insulation
• 1/2″ ZIP OSB Sheathing
• 2×6 SPF Framing at 600mm o.c.
• Cellulose Cavity Insulation
• 1/2″ Gypsum Board

• Roof Assembly (R60)
• Enviroshake Shingles
• 5/8″ ZIP OSB Sheathing
• Attic Trusses at 600mm o.c.
• R60 Loose-fill Cellulose Insulation
• 1/2″ Gypsum Board

• Windows and Doors
• Fiberglass framed, double-glazed, low-e (SHGC < 0.5, VT > 0.5, overall U-value < 2.0 w/m/K), argon filled, superspacer windows
• Insulated metal-clad wood entry doors

Mechanical / Electrical

• Space Heating and Domestic Water Heating
• Source: High-efficiency condensing boiler (high temperature DHW and low temperature space heat) with integral or external heat exchanger.
• Distribution: Hydronic Radiant Floor Slabs (all floors)
• Rough-in for future solar pre-heat and power.

• Ventilation
• Direct outdoor air system (DOAS) – dedicated ducted supply with Heat Reclaim Ventilation (HRV). Supply points in all bedrooms and living rooms, exhaust from kitchen and bathrooms.

I think the ZIP OSB sheathing is one of the more interesting products to be used in this project. It differs from regular sheathing in that, once installed, creates a perfect water barrier for your home, before siding is even attached. As a result once the sheathing is on, work can actually proceed on the interiors while work continues to complete the exterior shell.

Neat!

Massay University in New Zealand today announced a significant advancement in solar technology.

Dr. Wayne Campbell proposes a technique that uses nanotechnology to make photo-electric solar cells from dyes such as a synthetic chlorophyl. The cells would cost just 1/10th that of traditional silicon-based sells and use readily renewable and simple to process resources.

This adds more credence to my personal opinion that we will see a massive shift towards solar power generation in 5-10 years.

Unconnected to this announcement but on the same topic, Xerox PARC has posted an interesting lecture on the history and future direction of photovotaics.

Time has a posted parallel articles on creating earth-friendly homes and changes you can make in your lifestyle to reduce CO₂ emmissions and consume less power.

The solar-hydrogen home energy system designed by Mike Strizki (with half of the $USD 500,000 price tag covered by government grants) is a great first step, even if mainstream version of the system are at least a decade away.

The helpful folks at SESCI have pointed me to a web site that details the rebates available for those putting solar power onto the grid.

For each kilowatt-hour generated, the producer will be paid 42 cents. That rate is “set for the entire 20-year length of the contract.”

Since we only pay 10.3 cents to take the energy off the grid, that sounds like solar panels would be a LOT more affordable; even profitable! However, there are a few catches.

For example, “new contracts will be subject to review every 2 years,” which sounds a whole lot like the guaranteed term for the $0.42/kwh offer is 2 years, not 20. Additionally, to put power onto the grid, we would have to pay an $800 initial fee AND $800 per year. (There are efforts under way to reduce or eliminate this fee, but that’s how it is today.)

If we assume that energy costs will increase at a rate of 5% per year, and we will always use 4200kwh/year (for simplicity) our energy costs over 25 years will be $28,189.53 from Toronto Hydro, or $35,806.78 from Bullfrog Power. (This latter number isn’t quite fair since presumably wind power will not become more expensive to produce over time.)

Solar Panels come with the previously mentioned up front cost of $25,000 and we are assuming the cost of borrowing that money is 5%. We also have an up front cost of $800 to be a power generator and must pay $800 per year to put power on the grid. (These costs should probably also increase at a rate of 5% per year, but we’ll leave flat for this example).

[Update 2007.11.03: It seems our (relatively low-light) region would require us to purchase a $50,000 solar panel array to cover our current electricity requirements. I have not updated the numbers below to reflect this amount.]

Even if we assume we are consistently paid 42 cents/kwh over 25 years for power we put onto the grid (though I think it’s more likely it would actually drop) and we assume we would be buying power back at the market rates from Toronto Hydro, our electricity expenses on a solar home would be $49,336.80.

So the ‘incentives’ that were missing from the previous calculation actually revealed the additional costs involved in putting power onto the grid. Solar panels would appear to be 38% more expensive than just buying clean power from Bullfrog.

I believe these numbers now factor in all financial incentives, and the projected increase in energy costs of 5% per year.

The government of Canada has an Office of Energy Efficiency (OEE) which, contrary to what you may have come to expect from your government, has a whole lot of truly helpful information to offer!

In particular, they have a library of consumer appliances, complete with their Energuide ratings. They also list available rebates, statistics, regulations, etc. The site doesn’t just deal with valuable information for energy conservation at home, but also for business and on the road.

Well worth a visit if you are concerned about your energy consumption!

I first became aware of the Stirling engine when reading about inventor Dean Kamen many years ago. He didn’t talk about the Stirling Engine in detail, but what I did find out was that it is an incredibly efficient non-combustion engine, that is powered by differences in temperature. (e.g. you can buy small a Stirling engine that is powered by the difference in the heat from your hand and the ambient temperature.

Sounds great right? In our home, maybe we could generate heat on the roof, and take cool from the ground and generate some free power, right? As is often the case, the first tip-off that there might be a problem with this logic is that nobody has done so already.

I did a little more research and it seems that unless you can get a heat differential of about 300 degrees Celsius, a Stirling engine practical for powering a typical home would itself need to be about the size of a typical home. Stirling engine size is proportional to the amount of power one needs, and inversely proportional to the heat differential between the cold and hot sides of the engine.

Another problem would seem to be the noise. The seemingly inappropriately named WhisperGen of New Zealand specializes in producing Stirling engine water-heater/power-generator combination units. According to their literature, these devices produce 63dBA of noise (and only a fraction of a house’s power requirements). While that’s quite quiet for a generator, it’s still the volume of a loud conversation, or air conditioner. That’s fine if one is encountering it from time to time, but to have it going in one’s home all the time would likely get a little grating.

It might very well be possible to overcome the heat differential limitation, but given the noise they generate it seems unlikely that Stirling Engines can be a part of any urban sustainable build.

Alex had mentioned that as a general guideline, energy prices are assumed to rise on average 5% per year, even though they’ve risen 7% per year in recent years. I actually find it hard to believe this would be the case over a 25 year period. This would mean energy costs would be over 3x more expensive than they are today (without factoring in inflation) by 2031.

As energy prices rise, the viability of various technologies to make energy generation more efficient rises. But if we do assume this number is correct that just removes the interest portion from our calculation and results in a monthly cost for solar panels of $83.39, which is still more expensive than simply buying the power from Bullfrog.

This advantage might disappear if there were financial incentives offered for providing solar power to the grid, but so far I’ve been unsuccessful at finding any. I had heard that the price paid for adding power to the grid was significant, but have also heard from someone else that those incentives are no longer available.

In addition, when those subsidies were offered, there was no commitment as to their term. An incentive that can be withdrawn at any moment is not much of an incentive at all. I’ll have to investigate further.

Our fifth design meeting continued to refine the garret and the access to it. It now includes an area which will be open to the ground floor and should act as a large chimney to allow hot air to rise and vent out, in the summer. We decided a curved, narrow but fixed staircase would be the best way to access the garret (instead of a pull-down staircase that would be less stable). The area will also include a narrow walkway through open ‘chimney’ to get to the attic space at the front of the house.

I took this opportunity to discuss my previous ideas about the economics of solar panels with Alex. He had read the article and suggested I’ve messed up the math in a couple of ways:

1. I didn’t include the usual 5% rise in energy costs (5% is used even though energy costs have actually averaged 7% in recent years).
2. There was no allowance given for the financial incentives offered by the utilities.

I’ll continue the discussion of these factors in the follow-up to the solar panel post.