Off Peak Cooling in Colorado

As you study the costs of electricity generation, you find out that Xcel's cost go up sharply during hot summer afternoons.  Back in the days of off-peak, or TOU, rates, PSCO tried to pass the extra cost on to the customers.  This pricing scenario has faded out over the years, but may come back.

Evaporative cooling works best at night, so you can accomplish off peak cooling by overcooling your house at night  and in the morning.  The cheaper coolers hardly work with a daytime temperature above 86F anyway.  The thermal mass of your house will then let you coast through the afternoon without using air conditioning at expensive rates.

Green Backup Power

After Hurricane Sandy, having a backup source of power for your home has become more important to some people.  Using a gas generator is one option, and they are very economical to buy, but not necessarily to run.  After Sandy, it was tough to find gasoline.  Another option is to have a permanently installed natural gas generator, but this isn't a good option in an all-electric home.

If a lengthy power outage ever hits Denver, those of us with large PV systems will be kicking ourselves for not installing an easy way to go off grid.  You see, all the PV systems you see on private houses currently DO NOT WORK if the grid is down.  The average refrigerator has $200-$300 worth of food in it.   I'm allergic to most candles, and they are a great way to burn your house down, so backup electricity would be nice.

I'm sure that the big power purchase agreement providers, SunRun and Solar City, are working on this, and I'll post the answer here when I get it.

EDIT 3/18/13:  The inverter company, SMA, will be releasing a new inverter that has this functionality.  It will have "an emergency power supply to provide daytime power in case of a grid outage".
This is expected in 2013, so be sure to request it for your house.
The ultimate system will use your electric vehicle or plug in hybrid for electrical storage and backup power.
R. Carter Scott plans to do this, and I'm sure he'll report more about it.

LED Lighting Innovation?

110v LED light bulbs each contain some circuitry to make them work with 110 volts AC.
LEDs are happier with 24VDC.  LED bulbs also use just a small fraction of the power of incandescent bulbs. That means that the typical 14 gauge wire going to light fixtures will be overkill for LED lighting, and be a big waste of copper.

So, theoretically, lots of money could be saved in new construction if the lighting power and distribution system could be optimized for LEDs.

Lumencache.com proposes to do just that.  This is a great idea, but boy, high volume means everything to low prices.  Trying to change how new homes are wired will be an epic uphill battle against code officials, old building professionals, and timid homebuyers.

Video: Cold Climate Direct SDHW system with Recirculation Freeze Protection

I've mentioned this system before, and I finally made a video.  Please remember this is the first prototype system, and is intended to be temporary.  (It's ugly.)  Our current thinking is that the system isn't developed enough for general public consumption, but I definitely recommend it for do-it-yourself types in milder climates. It is literally the least expensive and most efficient system with freeze protection possible with off-the-shelf parts.

We've instrumented the prototype system, and are checking all the failure modes this winter and measuring the amount of heat lost due to freeze protection.  The video still raises many questions, so don't hesitate to ask them in the comments section here, or preferably at Youtube.

Smart Light Bulbs?

Phillips has recently introduced their HUE lighting system.   It's a wi-fi based light bulb control system for timing,  brightness and color.

How can you use it around the house to save energy?  Honestly, I can't think of any scenarios that would reap enough savings to justify a $60 bulb.

But in multifamily buildings, there's the hallway lighting to address.  In the middle of the night, the hallways could be dimly lit.  During the day, the lights could be completely off.  This system is competitive with the cost of hardwiring timers and dimmers.   And I've never seen dimmable timers.  You could save at least 30% of your hallway lighting cost.  Still, I'd wait until these bulbs come way down in price.  

Product Design and the Fluidmaster Leak Sentry FAIL

Here's a common sense tip when shopping at Home Depot - be very suspicious of buying any product when all the units on the shelf look like they have been returned:

Notice the shabby condition of all the boxes on the right.  The product is obviously a market failure.

It's a great idea - a toilet valve that alerts you to a flapper valve leak.   But somehow the way Fluidmaster has implemented it has turned off customers in a big way.

The Hydro-Clean model on the left is a copy of the Fluidmaster design, and doesn't appear to work much better.   The boxes are fresh only because it was recently introduced.

Now a little commentary on product design and market testing.   Fluidmaster could have saved themselves this costly market failure if only they had gotten a couple thousand out into the field for well-documented feedback.  They probably tested the heck out of these to make sure they worked as designed, and found it was a robust design.

But here's the problem:   They work DIFFERENTLY than what customers are used to.  Sometimes different gets rejected by the market even when it's better.

LED Lighting Update

IKEA has finally put its purchasing power and design talent toward LED lighting.

I think they hit it out of the park, and did it a year ahead of Home Depot.   In the catalog, they mention that the bulbs never need replacing.   Nice.

http://www.ikea.com/us/en/catalog/categories/departments/living_room/20515/