How much did I save? How many kWh did we use last month?

[bcroe]

I contend, first understand ones energy consumption. Next understand the options to improve
the situation. Then make a plan.

With a plan, no need to wait. This solar will outlive me, every year not operational is permanently
lost benefits. The PV solar might be installed in a few days or weeks, meanwhile appliances and
windows may be replaced, vampire loads tracked down, insulation added over the long term. That
stuff has seriously occupied me for a long time, and will continue. But in the mean time, my heat
and electricity purchases have vanished, my buildings are more comfortable, and I do not worry
about the thermostat setting or certain occupants leaving lights on.

I certainly do not favor just screwing in LEDs or maybe installing solar, with no idea of the energy
use picture or what can be done about it. Nothing is going to be a magic silver bullet. I am actually
dealing with such a situation on one of my volunteer responsibilities, too early to see how it will play out.
Bruce Roe

[discodanman45]

I'd go a step further and say that conservation and increased efficiency is almost always a better way to save money. Turning off unneeded loads, adding insulation, changing paint/windows, replacing old appliances etc is almost always the best approach at first. And if that doesn't provide enough savings, and they are in a good area for solar, _then_ solar might make sense. (And it will be cheaper to boot since it doesn't have to offset as much load any more.)

With the decreasing cost of solar, I am wondering what the price per watt would be for keeping old appliances/windows and just installing more solar. Replacing old appliances is expensive and uses more resources to make. It might be more cost efficient and environmental friendly right now to just install more solar panels and avoid green upgrades. Windows I could see as important because of heat loss and most heaters in my area still use natural gas.

[funguy11]

With the decreasing cost of solar, I am wondering what the price per watt would be for keeping old appliances/windows and just installing more solar. Replacing old appliances is expensive and uses more resources to make. It might be more cost efficient and environmental friendly right now to just install more solar panels and avoid green upgrades. Windows I could see as important because of heat loss and most heaters in my area still use natural gas.

For the majority of people it makes sense to install solar and improve efficiency

[jflorey2]

Replacing old appliances is expensive and uses more resources to make.

Yep. Same is true of an extra 2kW of solar.

It might be more cost efficient and environmental friendly right now to just install more solar panels and avoid green upgrades.

Maybe - but you have to do the math. And when I've done it in the past, 90% of the time it makes more sense to replace appliances first.

[discodanman45]

A 1990's 22 cf fridge uses 850 kWh a year. The top of the line 22 cf energy star fridge uses 425 kWh a year. That top tier energy star rating fridge would cost $1000. Your old fridge would maybe have a $50 selling value. At $0.20 per kWh it would save you $85 per year or 11 years to make back that money. In my area it would take about a 250 watt panel for that extra 425 kWh annual usage. After 30% tax credit, that would work out to be $2 per watt or $500 to run the less efficient refrigerator. The more I look at numbers it makes sense to just throw up extra panels on the roof. Most installers will also give discounts for installing larger systems as well. So that extra panel for that fridge may cost less than you think.

[J.P.M.]

For the majority of people it makes sense to install solar and improve efficiency

You have the order precisely backwards. And, (this will read like absolute heresy) believe it or not, there are more than a few scenarios where residential PV cannot be economically justified, and lots more where systems have been way oversized beyond cost effectiveness.

In most every case, for most bang for your long term buck, and in some loose priority:

Start with an energy audit. It'll probably point to:

1.) Stop wasting energy - start by turning stuff off, and/or lifestyle changes as appropriate. Think !
2.) Add conservation measures like sealing/insulating. Do the sealing first.
3.) Depending on what the energy audit finds, clean/repair old appliances. Start with cleaning/replacing HVAC filters and cleaning refrigerator coils. Replace cheap stuff like lightbulbs and thermostats first, but don't put off big replacements like fridges/A/C any longer than necessary.

4.) And, in the end, since PV is about the least cost effective way to reduce an electric bill, make PV the 2d last thing your do - if at all, before new windows - which may be nice, but usually can't be justified from an energy cost saving standpoint.

If long term cost effectiveness has any place in the priority of reducing an electric bill, common sense says do the most cost effective stuff first.

Throwing expensive PV at a high energy bill before doing all the more cost effective things to reduce the bill is doing it precisely backwards, but PV peddlers and their green wash media shills have most of the solar and energy ignorant public B.S.'d.

[bcroe]

Do not forget, the cost of the panel(s) might be only 25% of the total system. And the ancient fridge
(bought mine in 1971 used) may not have much life left. Bruce Roe

[discodanman45]

Do not forget, the cost of the panel(s) might be only 25% of the total system. And the ancient fridge
(bought mine in 1971 used) may not have much life left. Bruce Roe

My parents have a 1942 GE fridge in the basement and hook it up for beer/soda for parties. It has never been serviced and still works great. That 1971 fridge has been working for 48 years, it probably has more life in it than a brand new fridge you bought today. It is sad how they make things these days. They use cheap lightweight materials and everything has cheap circuit boards in them that last a max of 10 years.

[discodanman45]

Throwing expensive PV at a high energy bill before doing all the more cost effective things to reduce the bill is doing it precisely backwards, but PV peddlers and their green wash media shills have most of the solar and energy ignorant public B.S.'d.

Here in California with net metering I would have to disagree with you. You could throw money at solar and it may just be the most cost effective thing you could do.

However, I would agree with you that you should make every effort to reduce use before installing solar. I did as much as I could, but I am not replacing my HVAC unit. I have a 5 ton unit and it would be extremely expensive to replace and extra solar is way more cost effective. I make sure that I have it maintained every year and it is running efficiently.

[SunEagle]

Here in California with net metering I would have to disagree with you. You could throw money at solar and it may just be the most cost effective thing you could do.

However, I would agree with you that you should make every effort to reduce use before installing solar. I did as much as I could, but I am not replacing my HVAC unit. I have a 5 ton unit and it would be extremely expensive to replace and extra solar is way more cost effective. I make sure that I have it maintained every year and it is running efficiently.

First off not everyone lives in CA or even has a tiered power rate schedule as high as you do. For that matter most of the rest of the country pays on average about 11 cents/kWh. So please don't try to justify people should install pv before they replace old and inefficient appliances.

[bcroe]

I have a 5 ton unit and it would be extremely expensive to replace

I will be presenting that exact problem to the owners of a century old mansion, on the nat historic
bldg reg. They will need to decide.

The reasons for adding PV solar are extremely varied. Conservation is a diminishing returns
process, more and more effort gives less and less improvement. At some point solar can finish
the job, setting net consumption to zero. That is a big one here. Bruce Roe

[discodanman45]

First off not everyone lives in CA or even has a tiered power rate schedule as high as you do. For that matter most of the rest of the country pays on average about 11 cents/kWh. So please don't try to justify people should install pv before they replace old and inefficient appliances.

I was very clear that I was talking about areas with high electric costs and net-metering. Where did I say that this was for all solar installations? I even said CALIFORNIA!

[J.P.M.]

Here in California with net metering I would have to disagree with you. You could throw money at solar and it may just be the most cost effective thing you could do.

Opinions vary.

PV is always more cost effective when net metering is available, but that may be a bit misleading. Without net metering, PV is a fools errand for most residential applications anywhere, even including most areas where rates are high like CA.

Supply some logic to me that buying PV is less costly than not using/wasting power in the first place.

Or, that a PV system, even if it can be demonstrated to have a lower LCOE than grid power, can have a lower NPV cost of the savings from conservation measures.

I've been at this a long time and probably one of alternate energy's biggest fans. PV is fun and sexy, but it is simply not the most cost effective thing to do to reduce an electric bill, and therefore, in most any economic analysis it's about the last measure taken not the first. Making it closer to the first is backwards.

[SunEagle]

I was very clear that I was talking about areas with high electric costs and net-metering. Where did I say that this was for all solar installations? I even said CALIFORNIA!

Sorry. I did not mean to yell.

There are some members that live in CA that think everything revolves around them so all of their justifications for pv is a no brainer. I really wish pv could be easily justified throughout the US but even with the lower costs of hardware it is very hard to justify for me and others.

[jflorey2]

PV is always more cost effective when net metering is available, but that may be a bit misleading. Without net metering, PV is a fools errand for most residential applications anywhere, even including most areas where rates are high like CA.

Agreed - with the exception of Hawaii. With residential prices hitting 40 cents/kwhr, even zero-export systems often make economic sense (once the aforementioned efficiency improvements have been researched.)