Sie müssen Brand Viagra nur bei derviagra apothekeViagra Brand ist für jene Patienten nicht angezeigt, die eine andere Medizin gegen

Cialis is cheaper than brand pills, and you can always afford normal treatmentcialis onlineCialis online simply place your order, use your credit card to pay for your pillscialistaking erection pills to support your compromised erectile function (you will not have to take Cialis for the rest of your life.There is only one place to play from Online Casinos.casinoPlay Online Slots.Usually the recommended dose is 50 mg Viagra.ViagraViagra 100mg

Premature Solarization – Solar Power Before Reducing Consumption

by Nic Darling on January 22, 2009 · 21 comments

in Building Science,Philosophy,solar

Disclaimer: I am aware that solarization is used incorrectly in the title of this post, but I use it in an attempt to make a joke that is both juvenile and trite. Forgive me.

We are planning on attending a solar happy hour this evening, and that got me thinking about that most recognizable of green features, the solar photovoltaic (PV) panel. Sparkling atop roofs and drinking the sun to power our blenders and televisions, these conspicuous badges of sustainability symbolize a great hope for our energy drunk society. They hint at a power source that might save us from the dreaded consequences of our wanton fuel gobbling. We might, with their help, be able to plunge forward undeterred on our path of mega-consumption. Recycled Big Gulp container in one hand and the wheel of our electric Hummer in the other, we can speed forever down the highway of prosperity (or at least until that Big Gulp makes us stop at a waterless urinal).

Unfortunately, we are still a long way from this dream of boundless solar energy. The resource is there, a churning ball of nuclear fusion just 92,960,000 miles away, but our ability to harvest it is not. Currently the sun provides just 1% of our total energy consumption, and that number is increasing at a snail’s pace. President Obama (that’s nice to type) may indeed see us getting 25% of our energy from renewable sources in 2025 as he hopes, but very little of that is likely to be solar. It is expensive, challenging to integrate and in some places impractical. Also, our demand for energy continues to grow, outpacing new technology as it tries to catch up.

That said, those panels pinned to the roofs of the occasional green building are a beautiful thing. They are a bold move toward making the building a producer of energy rather than a consumer. They represent a potential shift in the way we think about energy delivery. But, they are just a tiny drop in a giant sloshing bucket. Worse, they are often just a drop in the bucket of the building on which they are perched. There are relatively few net-zero buildings out there, far less than the number wearing panels. The energy demand is simply too high. Many people have said it before me, but we need to reduce consumption to make renewable energy effective in the short term. Sure, someday in the future you might be able to leave every light on in your house with the HVAC at full blast and the windows open (so you can hear your music as you lounge in your giant heated pool) and know that all that juice is coming from the sun. But that day is not today.

When people visit our homes they always ask about solar panels (we have solar thermal but not PV). It is an inevitable interview question and an unavoidable conversation. The simple answer is that adding solar PV is simply too expensive. It isn’t in the budget. The longer answer involves a set of priorities which seek to minimize use before investing in production. Even if the money to install solar was available, it might be better spent on improved windows, more insulation and energy saving automation products. Solar PV becomes more feasible as we reduce demand. If the proverbial horse is reduced consumption while solar represents the cart, it seems that many people are still trying to get the horse to push. Horses hate pushing, and we try not to make them do it.

We will have solar PV on future homes (when the state incentives finally come through), and the homes we are building now can easily be retrofitted for solar power. I certainly don’t condemn anyone who makes the investment in solar, and I commend those doing the research to bring us better, more effective options. However, I think adding panels to a building that has not been designed (or retrofitted) to greatly reduce energy consumption is premature. Invest first in the building envelope and systems. Then add solar. It will be much more effective.

What do you think? What kind of potential does solar energy have for buildings? How efficient should a home be before the investment in solar will pay off? How does this extend to society in general? How much of Obama’s 25% will need to come as a result of reduced consumption?

If you have something to say . . . comment.

If you enjoyed reading this post I can promise you'll love our new writing over at Postgreen Homes. Yeah, we know that's the same thing your favorite band said and their new album is nowhere near as good as their early stuff, but seriously, we are actually still getting better.

There also isn't much conversation to be had here . . . at least not with us. So come on over to the Postgreen Homes Blog and tell us what you think of our new(ish) digs and crazy ideas. We will be sure to tell you what we think of your opinion.

{ 4 trackbacks }

Our Top 10 Priorities When Building a Green Home on a Budget | 100K House Blog
March 22, 2010 at 6:43 pm
The (solar) power of art. « Daily Design Idea
June 2, 2010 at 2:46 pm
On a Budget? These are your Top 10 Priorities When Building a Green Home « Courtland Custom Homes Blog
April 19, 2011 at 10:41 am
Save Nature And Your Capital Using Solar Energy | Solar Cells For Sale
October 24, 2011 at 1:22 pm

{ 17 comments… read them below or add one }

1 Darin January 22, 2009 at 11:43 pm

I’m certainly a fan of the direction you guys are headed. Using less resorces is better then trying to find a way to consume more…even if those resources are renuable. Keep up the great work!

2 Grant January 23, 2009 at 12:22 am

I was a bit aghast when I took the 2008 ASES Solar Home Tour here in Alabama.

A well intentioned man had just installed the largest residential grid-tied PV system in Alabama. It was easily a $100,000+ installation and he installed it just months before the solar tax credit ceiling was raised! I really felt sorry for the guy.

Not only that, but he was operating an inefficient electric water heater and saw no purpose in installing SHW… I tried to explain, but he said he preferred to power his old electric water heater with the PV.

He had made absolutely no attempt to reduce consumption before sizing his PV system. His attic was open to view some of the details of the PV installation, and he didn’t even have much insulation!!! No effort to put in new energy efficient energy star appliances… nothing.

Just a GIANT PV array covering every square foot of his solar oriented roof. He actually sells excess electricity back to the grid. He was very proud of “giving back” to society. He said he recognized he wouldn’t ever manage a financial return on his investment, but since he could afford to do it, he wanted to help the environment in this way.

Like I said, his intentions were good… But imagine what he could have accomplished with that much money if he had reduced consumption FIRST.

3 Jarsh January 23, 2009 at 8:29 am

Building a better envelope first makes sense but PV looks a whole lot more feasible wrapped into a 30 year mortgage.

4 Liza January 23, 2009 at 4:52 pm

Hello! Love your work! Small and responsible is definitely beautiful! There is a massive swing here in Australia towards community bulk-buys of grid-connected 1 kw solar pv systems. We have just completed one bulk-buy and have started on the next in my town! We have found that if people also install a small metering system, the desire to actually produce electricity and not use it all overtakes them and before you know it they are saving energy in all sorts of ways !!! It is a “chicken and the egg scenario” but I think that anything that starts the process of re-education and energy reduction whilst establishing a demand for a product, that perhaps needs improvement, but is a step in the right direction, has to be good!!! Until conspicuously wealthy individuals get with the “Smart New Frugality” there will be a desire for big houses as displays of wealth, but your website/blog is spearheading the movement to small, gorgeous and meaningful! Keep up the good work!

5 Kim Auger January 23, 2009 at 5:22 pm

Loved the post Nic!

Taking out a loan to do energy efficiency improvements could allow a homeowner to. . .

1. get work done to make their home more comfortable

2. reduce their carbon footprint

3. reduce their monthly payment to their utility company

4. most times their loan payment with their utility payment combined is less than their old monthly utility payment. (With the PECO rate caps coming off in 2010 this improves the homeowner money in pocket even more!)

5. The value of the home improves.

6. Now the home will need less solar pv.

Seems like a win/win no brainer to me.

ps. Solar thermal is always a better payback per square foot usage of a roof as it is more efficient.

I hope this is coherent. It has been a long day here in the office.

(I’m not an energy auditor in the firm, just the CEO)

6 David January 24, 2009 at 11:09 am

Jarsh and Kim make excellent points about financing the PV systems making them more cost effective. One more advantage to generating your own electricity is that you’ve fixed the costs over a long period of time. Electric rates from the utility companies ALWAYS go up. They don’t vary like the price of, say, gasoline. So your monthly savings grow over time.

7 Jerry Hajek January 25, 2009 at 8:51 pm

My $.02…
I think that the only way PV will begin to make an impact would be to include it into the design of a new home as a low voltage system to power lighting and any other ‘low demand’ appliances such as circulation fans. Low-voltage 12VDC systems have been around forever in the RV market, and are used for the above applications. The lights available are primarily fluorescent and halogens; there are incandescent bulbs available, but their lumen output is pretty lame…
Yes, this would require a separate service box for the low voltage system, but PV already requires battery banks and control systems that have to be integrated into the home power distribution panel and wiring anyway….
The previous is a PITA for an existing home.
For a new home, not so bad. One could potentially ‘double wire’ a home so that as newer, ‘solar friendly’ appliances become available, one could switch from VAC to VDC powered units with a minimum of retro-fitting.
Grants’ encounter in Alabama seems to validate what I’m driving at. For all of that gentleman’s’ best intentions and all of that money, the results for the effort expended will never be worth it. And his holding on to the old water heater just seems to compound the problem. And adding solar HW systems to an existing home is relatively easy compared to a big PV installation…
….and he didn’t do it! WTF?
….and few of us have 100K to throw at doing anything similar, and I would hope that anyone reading this blog wouldn’t follow that example of how to go about it…
What would I like to see? Well….
The 120K Home,V.2. Parallel wired for low-voltage systems. A ‘plug ‘n play’ PV panel system that would allow the new owner to add to the array as funds become available. ‘Hard points’ on the roof to make upgrades a cinch rather than a major undertaking. A similar approach to the battery bank and inverter system that could expand and (maybe….eventually….) ‘drive out’ the VAC ‘fridge and any other appliance that could utilize DC energy. In this way, consumers could ‘grow green’ over time. As a appliance needs replacing, one could switch over with less impact to the seemingly ever-contracting budget.
There will be a growing need for rational ways to implement PV systems into our lives. Since the whole thrust of this blog and the project and people that drive it, and their rationale for all their efforts, is to offer a truly rational alternative to people.
I appreciate and admire your efforts; I read your posts that catch my attention, and feel good that y’all are making a mark and getting some well-deserved attention….and, hopefully, Sales….
Carry on! Push the envelope; that’s what it’s there for…
(I’ll stop ranting at the choir now…dinner’s ready…)

8 David January 26, 2009 at 3:50 pm

I have to thank Jerry for pointing out something I do not hear often enough. I agree that low voltage DC should be included in a PV installation. LED lights run on DC. Items like computers, cellphones and PDAs all run on DC. The power supply just converts AC to DC. Why go through the conversion – TWICE? Using cigarette lighter-style outlets to tap into the DC makes it completely off the shelf.

It may come to the point in the not too distant future that only “legacy” appliances like current refrigerators run on AC; until they too are replaced by DC models. I thought about the only advantage of AC is in being able to transmit the energy over long transmission lines, and with an AC motor you eliminate the need for a controller.

9 Nic Darling January 27, 2009 at 10:59 am

Is parallel wiring necessary in a system that is tied to the grid? I don’t picture us using batteries in a house like the 100k any time in the near future. We don’t have the space. Any PV system would be grid tied. In such a case is there a reason for the extra wiring complexity?

10 Grant January 27, 2009 at 11:57 am


The advantage is in squeezing the most power available from the system. PV generates DC, which must be inverted to AC. LED lights handle DC natively. You save even more electricity when you power LEDs with DC. Appliances used in RVs frequently use DC natively. If you are relying on a native DC power source, it makes sense to have native DC appliances and fixtures.

Every inversion results in power losses. The more inversions of the power you can avoid, the more power for your buck you get. Also, it is always wise to avoid complexity wherever possible and inverters are complex systems that increase maintenance costs. The inverters are much more complex than additional wires…

If you can use DC fixtures and appliances, wherever practical, they are powered with less energy losses. Also, the DC power won’t go through the inverter and is not connected to the grid. That means they can remain live and useful during a grid power-outage.

On a separate note, recognize that a grid-tied system (without a ridiculously expensive battery back-up) generally is non-functional in a power outage. The power company requires the PV inverters to shut down to prevent back-feeding generated electricty into the grid which could potentially risk the lives of line workers.

There is actually a new PV inverter on the market that prevents feedback to the grid and allows dynamic disconnect and continued use of the AC inverted power from the PV panels during a power-outage. But good luck getting your local power authority to believe it . (Sorry, I can’t seem to find my bookmark on it right now, nor the email I sent to our local ASES affiliate about it.) Without such a new fangled inverter, the separately wired DC fixtures and appliances are the only ones that will work during a grid power outage. Even though your grid-tied PV panels are stilling functioning fine, without separate wiring they are useless during a power outage.

For me, avoiding complete power outage is a good enough reason for the redundancy. The reduction of inversion losses is just a bonus. But with such a new inverter that can keep your power live during a grid blackout (which should become more and more common), the only advantage to DC over AC is the prospective gains in efficiency. As high-quality DC fixtures and appliances become more common and more affordable, net zero houses will probably routinely employ them. Any house that remains heavily reliant upon grid-tied AC power, will likely continue to use lots of AC appliances and fixtures, because converting the grid AC to DC, will likewise cause losses. So which do you use more of: grid AC, or PV DC? Plan your primary power consumption accordingly to avoid losses.

If you don’t plan on generating the majority of the electricity used in your houses with PV, then AC makes more sense for most of the appliances. But you might still consider powering critical systems with DC, to keep them reliably running during a grid black-out and in the process squeezing every electron of efficiency out of your PV panels.


11 Grant January 27, 2009 at 7:42 pm

I finally found the bookmark… The inverter is called the Ecojoule system.

The theory sounds good. The big concern would be making sure to size the system properly for the critical loads you will connect to when the grid is down. A “brown-out” inside your home could get very expensive… I haven’t read deep enough to know how they isolate the critical systems and cut power to everything else when the grid goes down.

12 Jerry Hajek January 27, 2009 at 9:27 pm

Nic, ‘parallel wiring’ wouldn’t be necessary IF any electrician that was called upon to do any ‘future work’ on a system Really Knew What He/She Was Doing.
I don’t have that kind of faith…. I’ve seen some real questionable work on existing wiring, and PV integration will be a challenge for a lot of contractors in the short term.
If the light circuits are initially set up for low-voltage, there shouldn’t be a need to have a ‘parallel’ in that case; just an educated buyer with a proper set of specs so they don’t try to use the wrong bulbs.
DC circuits also tend to not require the same wire sizes that AC requires, but the NEC guidelines don’t deal with DC to any great degree. However, if one wires for AC, it would happily handle DC.
My rationale for parallel wiring on ‘other’ circuits’ is a point that David made: ‘legacy appliances’. It wouldn’t be a problem (in fact, frighteningly easy) to switch an AC circuit to DC. The inverse of that switch, made inadvertently, is what makes me feel that keeping the two apart makes sense and keeps the fire department and the legal types away.
And Grants’ right….if the grid goes down, your PV system could, at least, keep your lights on and some of the more desirable appliances up and running. Battery back-ups don’t have to be huge, either; just managed in a fashion that most people aren’t used to doing. Ask any RV owner about ‘dry camping’ (No water or power hook-ups, just what’s ‘on-board’; extra points for doing it without lighting up the generator….)
As for the local power ‘authorities’ (a term that will become redundant as newer technologies leave them running to keep pace), they’re just going to have to climb the same learning curve that inspectors are coping with in regards to SIPs’, super-strength concretes, and all the other innovations that make us smile and their brows furrow.
Tsk. *smirk*

Where to park the batteries? Hmmmm…
An SIP ‘doghouse’ off the back? You’ll need some room for the electronics anyway, and batteries like to stay warm….

13 tom toolbag January 28, 2009 at 10:48 pm

I have to agree with Nic about pv panels. If you do the math, it doesn’t add up. Further thinking would make me think: does the amount of energy and/or resources to produce them outweigh the lifetime energy production? If it weren’t for the rebates(subsidies) would the economics work… Then I look farther and think that the high entry cost limits the entry to a certain group of people. Then the excess energy is sold to a power company at a fraction of it’s true value, then that same energy is sold to their customers at the same rate as any other energy. To sum it up, taxpayer money subsidizes the purchase of pv panels and their energy output is sold for a fraction of it’s worth to the power company, then the power company sells it a a premium to their customers. WTF? That looks like a different version of the corn ethanol scam.
If you look at the need for energy, it can be broken down into a few categories. The term L.A.M.E. is a common way to do this.
M.E.-miscellanious electrical load
If you break these down further,
Lights- how many lights per/room, how many people in different rooms. How about a 1 or 2 lights on a track that can be moved to and lowered in the kitchen, to put the light where it is needed.
Appliances- look at the big power eaters: fridge, freezer, washer, dryer, stove, microwave. Is a double-door fridge really needed? why not have a fridge custom made(yes, it can be and is done) that suits your needs. Is a clothes dryer really needed? Can clothes be hung to dry without a dryer? Is the savings in the price of food offset by the energy costs for a freezer?
A dedicated system for the fridge, washer, and possibly for a furnace fan or boiler pump could and should be incorporated into a system because of the constant demand and the ability to keep the system basic. Battery technology has come a long way but still could improve. There is a company in Wisconsin that makes a zinc bromide battery that is pretty impressive, the name of the company is ZBB Energy Corporation.
I don’t want to imply that everyone should live like the “Flinstones”, but some actual forethought should be applied. Just look at the Amish communities, they seem to live rather well without a lot of energy consumption.

14 Marcus January 30, 2009 at 11:08 am

I love your work, and your musings on the subject. I always try to be an advocate for the devil in these eco-subjects, because the religion has swept so many unintelligent people up along with naive children who now preach the cause with no real sense of the problem….depending on how you phrase ‘the problem.’

blathering aside, I read something interesting, as I have been trying to figure out a way to build my own wind turbine…for shits and giggles, mind you, not to save the planet. please.

wind energy IS solar energy. the sun heats up parts of the planet, which makes air move, and then drop over cool parts of the planet, and voila… assuredly, this doesn’t help statisticians break down things for clarity, but the way you said it “the sun provides only 1%” is not, then, entirely accurate.
…if only I could split atoms, like I can hairs.

15 Jerry Hajek January 30, 2009 at 1:00 pm

You go, Marcus. If there’s any means to make wind (other than D.C. political hot air) create usable energy on every rooftop (yeah, I know it’s not constant….every bit helps, though…), it’s a windmill worth tilting. ;-)
I feel the same about PV installations. Small, large, and everything in betwixt, total net energy just might start to make a dent.

16 Grant January 30, 2009 at 1:36 pm

As long as you are splitting hairs, hydropower is also solar power…

And if you want to take an extreme to the point of absurdity, fossil fuels are also biologically stored solar energy -grin-. [I wonder if the Big Oil companies will have enough gall to ask Obama for subsidies on this basis... Wait... I shouldn't be giving them such ideas. They just might try, and Congress just might go along with it. -groan-]

17 Jerry Hajek January 30, 2009 at 1:46 pm

*LOL*, Grant. They’d do it in a heartbeat. ExxonMobil just posted yet another record year, so they don’t lack for balls ‘n gall.
I’m just wondering when we’ll all gather outside of their corp. headquarters with pitchforks and torches…..What a media orgy that’d be….

Leave a Comment

Previous post:

Next post: