Don't Worry About Swamp Cooler Water Consumption

People sometimes worry about the water consumption of an evaporative cooler.   I found this information in an NREL report:

"on a Btu-of-cooling-per-kWh-of-electricity basis, the best evaporative cooling systems are on the order of five times more efficient than SEER 13 central air conditioning (CAC) systems and demand is less by a factor of four or more. Further, additional water use at the site (home) amounts to only about 3 percent of the water use of an average residential customer."

So don't let water costs drive you away from swamp coolers in Denver.

However, if you are building a new, smallish, superinsulated low energy home, you are better off going with a mini-PTHP for heating and cooling.  A swamp cooler requires more maintenance and seasonal mode changeover, which is awkward due to seasonal overlaps like "Indian Summer".

Reports From the Field - Part I - Zone Valves in Apartment Buildings

EASY SOLUTION FOR ENERGY HOG APARTMENTS


Recently I have been performing energy audits of mid-size multifamily buildings, focusing on control problems, the true "low hanging fruit" of energy efficiency for these apartment buildings.


The most common problem we are seeing is zone valves that fail "open".   Tenants will not report this or complain about too much heat until summer.   In summer, no one is looking for boiler problems, and oftentimes the boiler is off for the summer, problem solved unknowingly.


This is not a trivial problem.   Just one zone valve that is fully open all the time in a building with constant circulation will waste at least $30/month.   We've seen 20 unit buildings using $100-$300 /month too much gas when this condition is present.


Landlords are cheap, but here's a situation where you have to spend a  little to save a lot.  The payback period will usually be under two years.   And don't forget:   Every $1000/yr saved in expenses makes your building worth $14,000 more in today's market.


Your average contractor isn't on the lookout for leaky zone valves.   He just wants heat in the apartments and no complaints.   And I can't tell you the reason, but Xcel Energy's energy auditors aren't trained to find problems like this.   


So that means you have to call me.  (720 435-5909)   Another guy in Denver who is great at this type of detective work is Mark Eatherton at 720 375-3107.


Here are my general recommendations:   

1. If you think that your zone valves are more than 20 years old, replace them ALL.   Seriously.
2. If they are more than 12 years old have someone check them out to see if any are leaking through.
3. If you have the 3-wire style zone valves "White-Rogers" more than 12 years old, replace them ALL with Honeywell or Erie valves.   It's not that they are  unreliable, they are just harder to work with.   The average maintenance technician has no idea how they work, so he can't troubleshoot them, and thus you will have to call a more experienced (read expensive) heating tech.
4. If you suspect your building is using too much gas or electricity, request a usage report from Xcel.  Contact the Building Solutions Center at  BSC@xcelenergy.com  or call  1-800-481-4700  .   Then email it to me at kevdickson@gmail.com and I will compare it to similar buildings and let you know if I think you have any problems.
5. Don't stop there.   Have your consultant look for other energy wasting issues - more on them later.

Denver's Street Grid is Efficient, Charming and Shouldn't Have Been Abandoned

A Rectilinear street grid is usually the most efficient layout for a city.

However, my observations of cities haven't convinced me that the grid is always the best form.  If you have lots of mixed use and high density, a grid makes destinations easier to find, and its porosity makes the perfect pressure relief valve for those peak traffic times.

Paris, Rome, and Sydney don't have grids.
They are interesting and walkable.  Historically, they were a bit hard to navigate for the newcomer.  GPS has fixed that, even for pedestrians.  Their streets grew organically around the topography and without much planning.  A grid for them would increase utility at the expense of charm.

There's an old neighborhood in Denver called Bonnie Brae that was planned in about 1910 and built out over the next three decades.  It has curvilinear streets, a diagonal collector road, but no cul-de-sacs.  It was designed this way because the private developer thought it would be more interesting, charming, and exclusive than the surrounding grid neighborhoods.  He was right, even though many backyards were reduced to skimpy triangles.

In the 50's & 60's this charm was noticed by the suburban developers, and they replicated the style in their new automobile suburbs, added gates, cul-de-sacs, and high speed perimeter thoroughfares.  The charm and walkabilty were utterly destroyed by the car-centric design.

So the grid makes city planning and development easier and more predictable, but folks will eventually get a little bored with it, and it doesn't make a better city by itself.

PS.  Don't ever make Denver's mistake of putting in one-way streets to expedite traffic.  Most of them have been put back to the way they originally were, two way.  Also never give in to the folks who live close to the thoroughfares and want traffic on their streets to be limited some way.  The extra traffic they suffer with a couple hours per day causes greater benefit of reduced congestion for the city as a whole.

LED Bulbs Now Available and Affordable

Spotted today at Home Depot, Dimmable!

Beyond Net Zero?

Now that a run-of-the-mill homebuilder can offer a net zero energy cost home, you might consider going beyond net zero.  Your house could generate more energy than it uses, and actually put money in your pocket.

How much could you make?  Well, according to these rules,  you can't install more than 20% excess solar capacity, and they will only pay you wholesale prices for it:




CALCULATION OF BILLING FOR NET METERING SERVICE
Net Metering shall be, for billing purposes, the net
consumption as measured at the Company’s service meter.
However, in the event net metering is negative such that the
Eligible Energy Resource’s production is greater than the
Customer’s consumption in any month, the Company will not
credit Customer for such negative consumption. The negative
consumption shall be considered as energy available to offset
consumption in subsequent months. However, in the event that
such negative consumption balance remains at the end of a
calendar year, Company will pay Customer for such negative
consumption balance at the rate that reflects the Company’s
average hourly incremental cost of electricity supply over the
most recent calendar year. Payment shall be made within sixty
(60) days of the end of each calendar year, or within sixty
(60) days of when the customer terminates its retail service.
Customer may make a one-time election, in writing, to have the
Company carry forward the Customer’s negative consumption as a
credit from month to month indefinitely until the customer
terminates service, at which time no payment shall be made by
the Company for any remaining negative consumption balance.


For new construction, you could make a high guess at your consumption, and maybe get away with more that the 120% limit.

Simplest Split Solar System Ever?

As you may know, I was originally trained as a Solar Engineer (solar water and air heating).  In the early 80's, we learned a lot of things on our own because:

1.  Manufacturers supplied only components, not complete systems.

2.  Because every house is different, every installation is unique, causing mistakes and "issues".

In my opinion, the solar water heating industry has still not  matured.  Because systems currently cost too much, they aren't being installed as often as they should (which is on every house in the Denver area).  For high volume uptake to occur, NREL says the installed price needs to be between $1,000 and $3,000, not the $6,000-$11,000 that you typically find.

Recently, I've been back to learning things on my own, and collaborating with folks like genius Steve Baer.
Some of us have been working on solar system simplification.  One simple domestic hot water system that  has tested successfully is depicted in the video on YouTube below.   If your house has the right configuration, I can install this system for you for $1850-$2600 with a 5 year warranty.  It may be simple, but it requires some high tech to succeed.  The collector we must use has the lowest heat loss coefficient of any mass marketed panel.

http://www.youtube.com/watch?v=Q5rKLsJl3cY

CFLs Suck Update

There is quite a bit of anecdotal evidence that CFLs can cause seizures, rashes and cancer.

http://en.wikipedia.org/wiki/Fluorescent_lamps_and_health

I know some people who "hate the light" from CFLs.   Since the color problems have been mostly solved, I think the subliminal flickering is what they object to.

Unfortunately, these problems are also shared with high performance T5 & T8 fluorescent tubes, which are very efficient and economical.  Affordable and long lasting LED tube replacement bulbs are coming eventually, so I'd still recommend tube fixtures where appropriate.