Do we still need rooftop solar panels when...

[Markyrocks69]

Ya you know what you can use land under solar arrays for? Houses. Build the house first and then put the array on top. It's like magic

[Ampster]

Ya you know what you can use land under solar arrays for? Houses. Build the house first and then put the array on top. It's like magic

Well, that brings us full circle to the OP's question.

[J.P.M.]

On building over roadways: That sounded/looked good to me until I thought it through. Things like safety/security, servicing, how to keep clean particularly if horizontal and over constant road/tire dust etc., all before cost and bureaucracy probably make the idea less appealing. Maybe those issues can be addressed in politically and economically effective ways.

Related to the problem solving, I'm seeing a lot of arrays over parking lots. I drive by several on a daily basis. Some are relatively large covering several acres. Such locations may provide some information and operational experience with relatively large, relatively high ground clearance arrays and perhaps begin to address some of the over highway concerns I see.

[JSchnee21]

Here in NJ, many folks were up-in-arms when Great Adventure (a local amusement park) wanted to clear hundreds of acres of brush, forest, wetlands to build a large PV array to save money and offset their carbon foot print. Especially when they already had hundreds of acres of tarmac parking lots. Of course parking lot solar canopies are much more expensive to install. Though, I do love parking under them. My employer has several at one of their main sites i NJ and it was so nice to come out to a cool, dry, clean, non snow/ice covered car. But, that employer ONLY installed them in NJ and not at a similar site in PA, because the SREC incentives in NJ made financial sense to do so. In PA it's not so cost effective. Most corporations are not in the business of hugging trees (-:

[J.P.M.]

Here in NJ, many folks where up in arms when Great Adventure (a local amusement park) wanted to clear hundreds of acres of brush, forest, wetlands to build a large PV array to save money and offset their carbon foot print. Especially when they already had hundreds of acres of tarmac parking lots. Of course parking lot solar canopies are much more expensive to install. Though, I do love parking under them. My employer has several at one of their main sites i NJ and it was so nice to come out to a cool, dry, clean, non snow/ice covered car. But, that employer ONLY installed them in NJ and not at a similar site in PA, because the SREC incentives in NJ made financial sense to do so. In PA it's not so cost effective. Most corporations are not in the business of hugging trees (-:

Yea. At the end of the day, and at the bottom line, it is and will continue to be about least cost/highest ROI, at least for businesses. Most consumers will probably never get the concept.

[ButchDeal]

. Of course parking lot solar canopies are much more expensive to install. Though, I do love parking under them. My employer has several at one of their main sites i NJ and it was so nice to come out to a cool, dry, clean, non snow/ice covered car. But, that employer ONLY installed them in NJ and not at a similar site in PA, because the SREC incentives in NJ made financial sense to do so. In PA it's not so cost effective. Most corporations are not in the business of hugging trees (-:

Actually it is cost effective in PA, just not AS cost effective as NJ. They had a choice and chose to to the more cost effective of the two options.

[jflorey2]

This area is best used for large industrial plants and solar thermal plants instead of PV.

Those are often found in such places as well. But PV is generally cheaper than solar thermal. So unless solar thermal has significant advantages (like thermal storage) that's going to favor PV over thermal.

Also note that a good deal of the southwest is were we grow the most food in the US.

You are talking about the Central Valley and Yuma. I am talking about places like the I-15 between Vegas and Barstow. There is literally nothing there other than desert.

And finally, if you try to generate power in southern California for use in NY you are going to have a lot of cost in transmission and quite a bit of loss as well, and we will need to built a great deal more transmission lines, thus it is much better to generate power closer to its point of use.

In many cases that will be true.

building over roads is quite a bit more costly than building in a field or on an existing roof.

Yes. But if is an area where land is very pricey it may well make sense. And if there are additional benefits (reduced road maintenance etc) then it might well be a net positive.

. Installing solar on the roof has been shown to reduce cooling costs in the building as well.

Agreed. There is an apartment building down here that has had an entire separate structure built to "roof" the building with PV without contact to the building's roof. They are also using gap seals. Not only will that reduce cooling loads, it will greatly extend the life of the roof (and likely the building itself.)

[ButchDeal]

And if there are additional benefits (reduced road maintenance etc) then it might well be a net positive

There will be increased road maintenance as there is now considerably more equipment in the road.

[Ampster]

This is what jflorey2 was talking about when he said water was one of the limiting factors in food production..

https://www.latimes.com/business/la-fi-agriculture-farmlands-solar-power-20190703-story.html?utm_source=SolarWakeup&utm_campaign=6bec6eb048-SolarWakeup_2_182_16_2013_COPY_01&utm_medium=email&utm_term=0_5eaa0aab62-6bec6eb048-44251225&mc_cid=6bec6eb048&mc_eid=1496ff781c&fbclid=IwAR2Sm-QvzoOQmLVxBbdpWB29XzgsH33n-XSkk_iOlh1bKfu2vpx7z8Xoarg

[macaddict]

Here in NJ, many folks were up-in-arms when Great Adventure (a local amusement park) wanted to clear hundreds of acres of brush, forest, wetlands to build a large PV array to save money and offset their carbon foot print. Especially when they already had hundreds of acres of tarmac parking lots. Of course parking lot solar canopies are much more expensive to install. Though, I do love parking under them. My employer has several at one of their main sites i NJ and it was so nice to come out to a cool, dry, clean, non snow/ice covered car. But, that employer ONLY installed them in NJ and not at a similar site in PA, because the SREC incentives in NJ made financial sense to do so. In PA it's not so cost effective. Most corporations are not in the business of hugging trees (-:

I've heard that the cost of steel and the SREC prices don't make solar canopies financial sense any longer in NJ.

[ButchDeal]

I've heard that the cost of steel and the SREC prices don't make solar canopies financial sense any longer in NJ.

there are other benefits for parking area solar canopies for businesses

NJ SRECs are still pretty good and the cost of energy in NJ is still high ( ~$230)

Companies are building parking canopies in other states with lower energy costs, and no SRECs because of the other benefits and commercial expense tax benefits.

I am surprised why most parking lots and roofs in DC are not covered by now though with their costs of energy and ~$400 SRECs

[Ampster]

Yea. At the end of the day, and at the bottom line, it is and will continue to be about least cost/highest ROI, at least for businesses. Most consumers will probably never get the concept.

Some businesses like the bragging rights. Public relations and goodwill are probably rationalzations why Target Stores have deployed more solar on their roofs than any other retailer.

No doubt there will be some consumers that will continue to fall for solar leases and other schemes. Often a simple payback period can be a justification. For the majority of consumers who use that tool to decide to put solar on their roof it really doesn't matter if they use sophisticated financial analysis for their decision making as long as there is some benefit. A simple 8 year payback calculated on the back of an envelope is far quicker than a Net Present Value analysis and often leads to the same conclusion..

[J.P.M.]

Some businesses like the bragging rights. Public relations and goodwill are probably rationalzations why Target Stores have deployed more solar on their roofs than any other retailer.

No doubt there will be some consumers that will continue to fall for solar leases and other schemes. Often a simple payback period can be a justification. For the majority of consumers who use that tool to decide to put solar on their roof it really doesn't matter if they use sophisticated financial analysis for their decision making as long as there is some benefit. A simple 8 year payback calculated on the back of an envelope is far quicker than a Net Present Value analysis and often leads to the same conclusion..

I doubt a back of the envelope analysis will produce the same result as a sound financial analysis that uses available life cycle costing or NPV analysis methods. The use or whoever is footing the bill may think so and in one sense, that's all that matters. But in another sense, given that most folks are financially ignorant, my guess is, and based on my experience, most folks are first of all following the same crowd that's not doing much more than running in panic from self inflicted high electric bills, and for the same reasons.

NOMB or concern, but while still entitled to an opinion, I'll have a hard time believing that back of the envelope logic is little more than a red herring excuse or justification for not doing a little due diligence. A few hours of self education can produce a better system that's more cost effective. If nothing else, doing so will confirm any suppositions which is usually all the back of envelope stuff is anyway. Not doing so is hard for me to understand except in the context of laziness. Guess that's just part of the prick engineer coming out.

Take what you want of the above. Scrap the rest

[Ampster]

I doubt a back of the envelope analysis will produce the same result as a sound financial analysis that uses available life cycle costing or NPV analysis methods. The use or whoever is footing the bill may think so and in one sense, that's all that matters.

How would any of the above analysis change the decision between two proposals, one with a 6 year payback and another with a 8 year payback. You have been asked that question before and never responded. EDIT: To make it simpler, how would NPV or other analysis change a decision about two equally configured proposals with different prices?

But in another sense, given that most folks are financially ignorant, my guess is, and based on my experience, most folks are first of all following the same crowd that's not doing much more than running in panic from self inflicted high electric bills, and for the same reasons.

Depending on one's cost of funds it doesn't take sophisticated financial analysis to make a wise investment that will reduce costs. You may be ignorant or arrogant about other people's financial abilities.

I agree in the case of a large corporation where due diligence is required, NPV and other analysis would be required. I spent many years of my career in that kind of environment where it was necessary for the shareholders or the financial institutions financing projects.

[jflorey2]

There will be increased road maintenance as there is now considerably more equipment in the road.

Well, no. Right now you have maintenance for the roads, and maintenance for the panels. By combining the two it is very likely that maintenance, as a whole, will go down. Maintenance will still be required for both - but by reducing/eliminating the requirements for salting and plowing, and by reducing the impact of rain (less water = slower pothole formation) it is quite likely road maintenance will decrease.

It is often said that in places like Minnesota, there are two seasons on the roads - winter and construction. One of the reasons for that is the effect of weather and temperature extremes on roads. The weather in Minnesota is very hard on roads, and reducing that impact could be a win/win.