Chris Kelly, ReVision Energy, Employee-Owner, Solar Design Specialist
The Sun may be the primary driver of Earth’s weather and climate, but it’s also a tremendous source of renewable energy through the science of photovoltaics. Chris Kelly of ReVision Energy will help us understand how photons from the Sun can help power our homes, businesses, and cars, with insights into what environmental variables solar designers take into consideration when evaluating different projects (including the weather!). Join the program if you’re curious about how solar panels work and how electrifying everything can serve as one strategy for combating climate change.
All right good evening and welcome everyone to Mount Washington Observatory science in the mountains lecture series my name is Brian Fitzgerald and I’m the Director of Education here at Mount Washington Observatory thanks so much for joining us this evening to tell us all about the science of solar power is
Revision energy solar design specialist and employee owner Chris Kelly who will join us in just a little bit here for those of you who aren’t already familiar with the Mount Washington Observatory we are a private nonprofit and member supported organization with ad mission to advance our understanding of the
Forces that create Earth’s weather and climate the way that we accomplish that is through operating our Summit weather station and remote sensing equipment around the clock with weather observation and forecasting Services by conducting research and product testing projects and by offering Innovative educational programs if you have questions for tonight’s speaker and
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Who’s joining us and who’s in the audience uh so right now I’ll go ahead and launch a poll question if you’re on Zoom with us tonight you’ll see just two questions here one we’re curious where are you joining from perhaps it’s a state within New England perhaps you’re
Joining from outside New England or perhaps you’re joining from outside the good old us OFA and then always curious as well uh he from a lot of different folks and I’m always amazed how many times people are joining for the first time and compared with people who’ve
Joined us for quite a while now we’re curious if you’ve joined us for a science in the mountains program previously so either yes I attend regularly yes but maybe just one two or three times or no this is my first program so I’ll give you all just a
Couple more uh actually just about 10 more seconds here to get your responses in looks like most of you have responded already so we’ll close the poll in about three two one alrighty and we’ll go ahead and share those results with everyone on Zoom it looks like New Hampshire is well
Represented there with almost half of you joining from the granite state and some good representation across New England no one from outside the country today what a shame um but good representation all around including outside of New England and then for those of you have you joined a science
In the mountains program before wow almost 70% of you have attend regularly we’ll welcome we’re so glad that you can join us month to month for these uh these great programs and happy to have you back uh for those of you who are just joining for maybe checking in here
Or there welcome to you and hey for eight of you it’s your first science mountains program welcome we encourage you to to check in whenever you see a program that catches your interest Al righty well we’ll go ahead we’ll stop sharing those results there and without
Further Ado I don’t want to take any more time away for our speaker this evening we’re really uh gracious that uh he’s here to speak with us tonight his name is Chris Kelly he’s a solar design specialist and employee owner at revision energy so Chris feel free take
It away welcome to the program if you can see and hear me all right hey I can I can see you that’s good that’s a good start can you hear me and I can hear you awesome well hey take take it away it’s all you all right thanks Brian and uh
Hello everyone thanks for joining tonight um little bit about me I’m I’m a a solar design specialist at revision energy like Brian said um so I work on our residential team at revision energy so I work with homeowners um go out to site do evaluations of their homes for
Uh for viability for solar projects we also do heat pumps uh battery storage heat pump hot water tanks EV charging and stuff like that so work with with regular folks to to try and um you know lower their energy bills and uh um reduce their carbon carbon footprint a
Little bit about our company we’re 100% employee owned certified bcorp we just turned 20 this year and we have locations in Maine New Hampshire where I live now and Massachusetts I saw there were a healthy number of you from Connecticut shout out to you guys go
Huskies that’s my home state so um I’m gonna jump in here uh share screen let’s see I’m hoping you guys can see that yeah looks looks great Chris sweet um so gonna keep this relatively high level full full disclosure I’m not an electrical engineer or anything
Actually was a a high school special ed teacher for for about four years back in Conneticut before making a change in career um and I’ve been with revision uh about four years now so um I’ve learned a ton and the company is incredible for for all kinds of of reasons but the
Training we receive is really is really topof the line so I’m going to share a little bit about you know the actual science of of photovoltaics how we actually turn um you know turn photons into electrons that we can use here on Earth and then a little bit about the science
That goes into kind of evaluations for solar projects which is a little more of what I do um so we’ll just jump into it here let’s see so photovoltaics um I want to say it’s it’s you know Greek uh photo meaning sunlight like photosynthesis and voltaics uh referring to electricity so
You know Soo solar photovoltaic panels you know basically take photons that are being sent uh from the center of our solar system 93 million miles away and use them to knock loose uh electrons um in solar panels uh that we put on our our homes and businesses um so we use those electrons
To power the systems of our home power the systems of our businesses schools and increasingly even cars bikes and all kinds of other devices here’s a a kind of a a larger uh version of that cross-section here so you can here you can see kind of
A generic solar cell you know we’ve got a a glass top sheet with an anti-reflective coating some conductors and then uh you know a negative conductor and a and a positive condu uh conductor and then the magic really happens in in the semiconductor the the silicone um
Uh the silicon crystal there um so there’s different kinds monoc crystallin poly crystallin um and there’s you know one of the crazy things about our industry is and one of the reasons that that costs for solar have dropped so rapidly uh over the past couple of decades is
Because the the R&D has really been incredible and you know you’ll see a little bit later in the presentation I’ll share a couple of photos of my system at my home about three three years ago and we have 360 watt panels on our roof and today if
I were to come to your home and quote you a a you know proposal most likely I’d quote you a 405 watt panel but there are residential panels 420 425 Watts so the underlying technology of how we actually get those photons to knock loose the the electrons in the outer
Ring of these atoms you know that remains unchanged largely but improvements in manufacturing and efficiency and things like that um you know have led to not only cost declines but also improvements in just the performance of solar panels themselves so how does it happen so photons strike and ionized semiconductor
Materials in the solar panel causing the outer electrons to break free of their Atomic bonds and due to the semiconductor structure the electrons are forced in One Direction creating a flow of electrical current solar cells are not 100% efficient in crystall and silicon solar cells in part because only
Certain Light Within the Spectrum can be absorbed some of the light spectrum is reflected some is too weak to create electricity that’s the infrared spectrum and some in the ultraviolet Spectrum uh creates heat energy instead of electricity uh fun fact about us as a company revision energy started about 20
Years ago um up in very rural Maine doing solar thermal projects so uh we were basically using the sun’s energy to heat up uh uh I think they were using glycol this is before my time but but some type of refrigerant running that through a loop and then a heat exchanger
To actually provide heat to people’s homes or to their hot water uh we have since transitioned exclusively to to solar electric photovoltaics uh you know largely because you know that’s just where the world is headed we can pair solar with Hyper Efficient Electric Heating and Cooling like heat pumps and get the
Desired effect but we do still service our our solar thermal installation so a little bit of solar history and um I promise I’m not going to going to read all these slides to you uh the the photovoltaic effect was first observed as early as 1839 and then really in uh 1954 is where
Kind of modern PV got its start uh you know you can read there the the First Solar device that produced a usable amount of electricity uh in 1958 um and solar was being used in a a number of smallscale scientific and Commercial applications um in the oil crisis of the 1970s you know
People were looking to diversify uh uh you know the the forms of energy that we’re using not only to get around but to to to produce electricity and this is where Interest really started ramping up and you started seeing a lot of uh investment in R&D you know certainly through NASA and
The Space Program you know we can’t run an extension cord out to space so uh the space program did a lot of um of R&D on solar and really made some huge leaps there and Industry developments and research in the following years made PV uh more feasible and a cycle of increasing
Production and de decreasing cost began which continues today so solar panels make DC direct current electricity our homes most of us unless you’re truly off- grid meaning you don’t have a connection to the uh to the electric grid uh like your neighbors your home is almost certainly running on
AC uh alternating current um you know so as I said solar panels make DC our homes run on AC so we use inverters to make this conversion there’s two kind of different design routes we can go down micro inverters where the power is goes from
DC to AC at the module level at each individual solar module and then AC wires run back to the point of interconnection or um you know we have a centralized inverter where we’re running DC back to a centralized inverter uh and making that conversion there you know
Without getting too far down the the rabbit hole you know that design we have what’s called uh uh DC optimizers which kind of improve the performance of of those types of systems here you can see um uh my basement so I don’t know if if you folks Brian can you
See my cursor I can it’s a little bit faint but a little bit a little bit yellow there yeah on the yeah okay perfect so you can see two inverters here uh one for each of the arrays on my home we could have gone with one inverter I actually didn’t design this
System you’re not allowed to design your own systems and sell it to yourself uh in the company so I had somebody um you know when I was pretty early on designed this for me but it works perfectly fine you you’ll see later I live in a 9 window Colonial here in
Manchester and we’ve got two different roof planes in parallel planes so same pitch although uh different planes but still parallel and one inverter one’s a 3.8 KW AC inverter the other is a 7.6 KW AC inverter we’ve got a combiner panel here I’ve got a couple of batteries in
The garage so this is what’s called a Tesla Gateway that’s basically a um you know smart ATS uh uh automatic transfer switch so this is kind of the brains of the system what you see here is the feed coming in from from the meter our main breaker is actually now
In this Gateway and then uh we’re connected into our main service panel where most of our loads reside and then we have a a heavy loads panel so these there’s a few circuits in here some heat pumps that we have which are great when the the power is up and running 99.9% of
The time but if the grid were to go down even though super efficient heat pumps have a pretty big Power draw and would drain those batteries pretty quickly um so they are in here and they get dropped in the event of an outage so that’s kind of what electrical infrastructure might
Look like after a solar install so here to there from the solar panel to the waffle iron so we connect the panel together in an array it’s very rare that someone might have at least on their home or business a single solar panel so there there’s there’s typically
Multiple solar panels wired together um and then we Conn interconnect those system those panels into the home or business’s existing electrical system now sometimes we need a a a panel upgrade or a service upgrade to get more power from the grid uh from the utility grid but typically um you know for most
Folks we can directly connect to their existing uh infrastructure that that’s typically done two different ways for larger systems you’re doing what’s called a supply side or line side tap where we’re actually tapping the feed uh from the meter above the main breaker uh so it’s Downstream from the meter
Upstream of the main breaker and then the electrons that are coming off the roof when the sun is shining is going right onto that onto that cable and feeding all the loads as they would normally be fed um from the grid uh on smaller systems and this kind of depends
On the the bus bar rating the size panel you know a number of different variables but it is possible sometimes to back feed we can install a breaker that is uh connected directly to the bus bar and the inverter can back feed through that breaker onto the bus bar bar um but we
Are kind of limited there by code and by by kind kind of the the the um specs of of the system um from there electrons produced by the solar flow normally as any electron would to where it’s being you know called by low demand so in a practical uh sense it
Kind of works like this anytime the sun is out our panels are making power now how much power they’re making is dependent on a couple of variables and we’ll get into a couple of these variables in a little bit but basically what time of day is it so where is the
Sun in the sky in relation to you know how that solar panel is existing in the world um what are the conditions outside obviously it’s nighttime now our solar panels are not producing anything right now but on on a beautiful sunny day in the middle of the day we’re making power
The first responsibility of any power that we’re making any electrons that are coming off the roof is to go to whatever the load demand is in that moment so we’re almost never you know kind of in Phase we’re almost always producing more than we’re consuming or consuming more than we’re producing so
In a scenario where we’re we’re producing more than we need maybe we’re at the beach in the middle of a summer day you know the fridge is on there’s a couple of things drawing uh but we have a relatively low demand you know any excess above and beyond the loads that
Are already being Satisfied by the solar is being pushed back out into the grid for our neighbors to use our meter is keeping track of that similarly like right now I have my lights on I have my computer on the sun is not shining we
Are still tied to the grid uh so we are still you know importing electricity from the grid and the meter is keeping track of that as well so just to kind of set some um you know some groundwork here this can be kind of confusing but Power versus
Energy power is the ability to do work so here we’re talking about electrical power you could also have mechanical Power but that’s basically the the ability to do work power is me measured instantaneously um and it’s measured in units that we call Watts so you may have heard of kilowatts that’s a thousand
Watts a megawatts a megawatt is a th000 kilowatt a gwatt is a million kilowatt and then an energy is power over time so that’s measured in units called kilowatt hours so this is this is actually what you get build for on your electric bill not power but energy so you’ll see kilowatt
Hours in a monthly billing period on your electric bill and that’s basically how much power you’ve used over a set period of time so one kilowatt hour uh could be you know uh drawn any number of different ways so you could run something that consumes a thousand watts
In real time continuously for one hour and you have consumed one kilowatt hour or you could consume one kilowatt hour of energy by running your home at 4,000 watts continuously for 15 minutes so another way that you know I like to kind of explain this to people is it’s think
Of it like um you know like uh you’re at your your kids or your nephews uh your niece’s soccer game and they have a big one of those big Gatorade jugs and think about this in kind of a battery uh uh application we’re installing more and more batteries so that people can save
Up the power that they make or the energy that they make at night and discharge those batter or the day and discharge the batteries at night so the volume of that battery is kilowatt hours is energy so that’s how many gallons are in that Gatorade tank how long it lasts
You though how long it lasts you is directly related to how wide open you open that tab so that Gatorade cooler can last a long long time if we’re taking little sips bit by bit but if somebody comes off to the sideline at halftime and opens up the tap and fills
Up their their cup and then walks away and it’s just gushing a ton of Gatorade it’s not going to last that that long so energy is what’s stored in batteries and batteries um output power in the moment um so common types of solar installations you’ve got residential rooftop installations that’s the market
I work in and then we’ve got commercial industrial and institutional rooftop uh uh installations those typically have some some differences uh they tend to be larger than private homes uh you know a lot of times they’re on flat roofs industrial you know Warehouse roofs so the way they’re actually mounted to the
Building is different and then of course ground mounted systems and we’ve got a number of different ways uh that we can install those there’s linear racking sometimes you’ll see single or dual AIS trackers and then utility scale which is just really really big solar arrays um
That are that are kind of act as as uh power plants onto themselves we’ve got some examples here here’s kind of a linear racking system just speaking for for our company personally and this is not you know this is not a um this not an infomercial so
You know um not here to to um sell you on our company specifically but we’ve made the choice to basically stick with linear racking generally you know the the efficiency of of the panels is getting better and better all the time and you don’t have the mechanical complexity especially of a dual access
Tracker where you know a dual access tracker which I’ll show you an example of that in a moment there here on your right dual AIS trackers which track on the Y AIS uh uh um annually you know over the course of the year and then on the x-axis throughout the day trying
Tring to maintain that that perfect perpendicular angle to the sun which is where we get the most power out of these solar panels and then you can see a single axis tracker so this is just tilting um ever so slightly throughout the year uh up and back um then you’ve got ground mounted
Or utility scale solar so these are typically um a lot of times they’re what’s called uh in front of the meter meaning there are no loads uh at the the actual location whereas at a home or business the solar is actually behind the meter so the first responsibility of
The electron the electrons we’re producing is to go to whatever the load demand is and for a lot of municipalities you know um just as an example their biggest load demand can be you know if they have any type of pumping any Wastewater uh treatment centers or anything like that pumping
Water takes a ton of electricity so the more uh generation you can have locally to to feed that electrical demand without ever interacting with the grid is where you can see some of the the um the greatest Financial benefits uh here’s our dual AIS trackers
And then you can see kind of an example of a a commercial uh roof right there you know I don’t know where this is maybe a um you know a warehouse of some kind but you can see these these panels are um you could walk through uh these roads
But they have a a much lower pitch you know maybe 5 to 10 degrees um but you can obviously fit a lot up there in a big big roof there’s my house home site home so as I mentioned um you know nine window Colonial so we’ve got two uh arrays there on Parallel
Planes uh we have 38 360 watt panels for a 13.68% with 11 Point 11.4 KW of AC inverter capacity um so here’s kind of what I do on a daily basis uh I evaluate people’s homes uh for solar and I think about it in kind of a couple different ways
Number one I’m an educator I help people better understand these Technologies how you know how they work uh how they integrate you you know uh into into somebody’s existing electrical infrastructure and then I’m also doing uh energy modeling and financial modeling um so I’m really there to be a
Resource to answer questions and then to collect accurate data which I can then apply to the modeling so people can um you know take a really sober look at their opportunity and evaluate it on their own terms for some folks um they’re very uh environmentally minded other folks are almost exclusively uh
Um you know economically minded but the the nice thing about that is it’s really two sides of the exact same coin you cannot have a uh very sunny optimally cited solar project and have kind of bad economics right you you can’t get one without the
Other um so I show show up I talk to people about what their goals are and then I look to collect a number of data points and understanding these variables which are unique to each different home um you know we can predict with pretty good accuracy what a solar AR array
Would be likely to produce in a given year the consumption side of things that’s a little trickier we try and use you know at least a year of historical uh uh electrical consumption data but you know um we are electrifying Society beneficial electri electrification if you’ve heard of the Electrify everything
Movement you know um we anticipate load growth um across all different kinds of sectors and for all different kinds of reasons home heating Transportation all that stuff so what are those important variables latitude where are we on the planet ath what direction uh on the compass are these solar panels going to
Be facing and then roof pitch or if we’re looking at a ground Mount what is the optimal pitch for uh for solar installation based on your latitude and then local shading right do you have trees or maybe a neighbor’s house that may be casting shade uh onto a potential
Roof plane or location for a ground Mount so what is latitude this is pretty basic you know it’s a coordinate basically showing in relation uh to the North and South Pole on a spherical Planet you know where you are right so you can see in the diagram the equator is at 0
Degrees Tropic of Cancer is at 2326 North you can see right here I just went and uh we’re at about 4427 North at the observatory up on uh the summit of Mount Washington so latitude helps us understand how much sun Sunshine Falls in a certain place on
An annual basis now this doesn’t factor in uh local weather patterns and certainly you can uh it’s perfect example uh um you know Mount Washington right there’s all kinds of places around you know North America that are at the exact same latitude as uh the summit of Mount Washington but have vastly vastly
Different uh uh weather patterns microclimates things like that so we want to be conscious of that but but at least that tells us how much Sunshine is actually falling at that Latitude whether or not it gets through or not that’s a different story um The closer
The poles we get you know the shorter the days get in the winter you know here we’re just a couple of weeks uh uh you know from the shortest day of the year so based on wherever that solar installation is going to be on Earth We’re factoring in
Latitude here you can kind of see and example of um latitude isn’t the only uh Factor but this is a colorcoded map of the power potential uh for PV installations um worldwide so you can see a number of different things are are taken into consideration you can see in
The northern wh in the northern hemisphere here we’ve we’ve got a a lot of green but you can see even along look at 45 degrees north halfway between the Equator and the North Pole you know and there’s a lot of variants right there haido I don’t know if we have any skiers
Here that is a somewhat of a mecca for uh powder skiers Hokkaido is one of the snowiest places on Earth and yet here we can see at the exact same latitude in inner Mongolia we’ve got a much much greater solar resource uh potential there here you can see in the United
States so you know you wouldn’t think it but again latitude is just one factor we have effectively the same potential in Southeastern New Hampshire Coastal Maine Massachusetts stores Connecticut my hometown as Houston Texas so you might not think and in fact we often hear people say oh solar doesn’t make any
Sense in New England you know we don’t get enough Sun well that’s that’s not exactly true um it’s about more than your latitude uh and so another thing we factor in is is asmith what direction is this roof facing that’s the angular meas measurement in a spherical coordinate system which represents the
Horizontal angle from a cardinal direction right so here in in New England I want to say Boston is about4 degrees uh solar South and Portland Maine is about about 195 so um that gets into kind of magnetic declination and and kind of true versus magnetic and and all of that stuff but
Suffice it to say um if you’re facing south you’re in a really good place but even East and and west facing roof planes you know if they’re not uh too terribly shaded can still be very very very productive um and the northern osphere solar systems are more productive the
Closer they’re facing to South obviously this is just the opposite for our friends uh in the global South the north side of your roof would be the most optimal down there uh roof pitch or just pitch uh of a ground Mount and this gives us an understanding of you know when these
Arrays are going to be at Peak power um you know throughout the year a soul solar panel is most productive uh when the sun is hitting it at a 90° angle um that’s a very very small percentage of the time right so on the y axis it may only be a couple days
A year and then depending on the asouth of your of your roof uh you know you may never get to that that 90% or that 90 degree angle on the x-axis at certain points of the year it’s possible um you know here in the Northeast and in other sloi locations we also factor
Factor in um or think about the pitch when doing our modeling based on snow loads right not only whe whether a roof will pass a structural analysis which is required here in New Hampshire um but also we’re thinking about how long would snow potentially stay on the
Roof here you can see my house again this is the first winter we had our uh our uh our solar array this was actually a um just about this time uh 2020 it was a stor big storm uh between Thanksgiving and Christmas and that you can see we had some wind
Loading uh on the south side of our roof and this entire slab slid as one piece um you know so depending on the pitch of your roof uh that’s going to deter and you know consistency see of the snow and some other variables that’s going to determine how long snow remains on on
Those solar panels and we’re going to factor that into a production estimate if you have a very very shallow pitch roof in the winter time you can expect that that um you know that snow to stay there for a long time uh again to any of
My skiers out there if any of you are like me you got your uh your Avalanche uh certification up on Mount was Washington Tuckerman Tuckerman Ravine and and um you can see here and this is not you know there are other variables but basically you know if you have a
Really steep pitch Roof then that snow is going to Slough very very often right if you have a very low pitched roof it may not Slough at all you may have to uh rely on it uh you know melting um and just in our own modeling you know we
Factor in historical weather data uh as well how we doing on time 36 wrap this up so we use a device called the sunai so you can see down here I’ve this is for my roof inputed uh or input a little bit of data we have a a 32 Degree
Roof my roof is facing about 175 degrees on the compass and what you’re seeing here on the xaxis is 6: a.m. 8:00 a.m. 10:00 a.m. noon and so on the camera it’s a fisheye lens but pointing it south and then on the Y AIS you can see months of the year so based
On wherever these shading obstructions fall within the frame of the photo in this path you know representing the sun’s path throughout the year we can get values uh you know based on these these shots from around the roof and use that as a a basis for our production estimate
Here you can see some some trees on the east side of of my yard that um and this time uh of year you know in uh around you know 9:30 to to 11 you know uh we’re getting some shade from this enormous white pine in my neighbor’s yard so this
Is how we we you know quantify um you know the amount of sunshine that would fall on a roof we also have uh you know in increasing liar coverage so liar is is like radar but with light so planes or I guess you could do it from a helicopter fly
Overhead and shoot beams of light down and they reflect back up and based on the time it takes you know to come down and back and back up you know we can do some really uh impressive mapping of you know um I know ecologists are using this
For mapping Forest canopy and and snow scientists are using it to actually penetrate snow to get snow depth uh things like that but we can use it in the Solar world to to quantify uh how much of an impact you know a tree or neighboring building might have so you
Can see here’s my house made a little 3D model and you can see the colorcoded um nature of of the roof shows you where the shadiest parts are so here you can see these panels right there are the least productive on our entire roof because starting in you know
Know mid to early afternoon depending on the time of year you know the these panels uh get encroached upon by shade from the upper roof um first and uh this is the last slide this is I thought you guys might be interested in actually seeing an installation so this is a little time
Lapse of my roof some of my co-owners come and put the feet onto the roof lay out some rail you can see there’s vertical rail on the very top row because we have some panels in landscape orientation on the upper roof you can see everyone has a harness and an anchor
Safety First Never Last have a future not a past and uh there they go one by one panels get wired up placed attached to the rail and uh what you don’t see is uh the electricians doing the the interconnection down in the basement and uh that’s really it so
That’s kind of a snapshot of how we evaluate uh sites for for solar so I’ll stop sharing my screen and Brian if you want to hit me with some questions yeah oh I’d love to thank you so much Chris that was um awesome awesome information really appreciate that and there um
There are some great questions some really thoughtful questions already uh been submitted and for those of you uh who’d like to get a chance to get your question answered by Chris feel free if you’re on Zoom make sure you use the Q&A button and we’ll just try and get as
Many questions as we can we got a little bit of time here so as long as you’re happy Chris we got some uh interested parties here including we’ll just start right out the gate Doug ask hey do solar panels produce electricity when it’s cloudy well yeah yes um depends on how
Cloudy uh certainly you’re not going to make as much power you know as a bluebird day um but yes uh solar panels will there’s still some light getting through those clouds um you know so you will see still see some power uh being produced you know um but again it is
Kind of dependent on how thick is the cloud cover and what time of day you know all those variables that we talked about earlier but but yeah we can still produce on cloudy days nice um apologies if I pronounced her name incorrectly but Alita um asked a question around brands of solar panels
Um what brands do you guys typically work with what are some other brands that Alita is asking specifically that you might recommend and maybe why um so I hesitate here like I said I don’t want this to be an infomercial for for revision you know I I truly
Love um this company it’s it’s an incredible we’re we’re an ESOP um 100% employee owned we’re a bcorp we’re a mission-driven company we’ve got an incredible incredibly High BC Corp score if you don’t know what a BC Corp is it’s a you know kind of distill it down to kind of the people
Planet profit kind of the triple bottom line so we make every decision based on what’s good for our our employee owners our communities that we work in the world um we’re not a nonprofit We Do try to make money no money no Mission some sometimes you you hear people say um
What I would say is there’s a lot of really good solar panels now you got to dig pretty deep in the crate to find junk um you know I encourage people to to really just vet the the installers that you’re working with I saw last month Time Magazine had a um had a
Really interesting article about it was something about solar sales Bros and you know how Shady contractors you know really threaten industry so I would say don’t don’t get too deep into the Weeds on the actual components because they’re all pretty darn good at this point I’d
Spend more of my time vetting who you’re actually going to partner with uh for your installation um so that’s what I would say yeah that’s great appreciate your transparency on on that piece as well um this is this is a good question from from David I’m not sure if you
Covered it as one of the many variables that you look at in a potential project especially the residential side of things how David wants to know how does roof condition especially age factor into an installation um how does a panel array affect an underlying roofing system yeah kind of it kind of depends
On what the roof system is so most typically what we see in this part of the country and this does vary a little bit you know depending on on you know can be hyperlocal you know if you drive um my parents live in the adx you drive
Up and over the Green Mountains you’ll see a lot more metal roofs same thing up in the in in the whites Mount Washington Valley down here in Manchester predominantly you know in Southern New Hampshire Massachusetts Southern New England um asphalt shingle roofs so really kind of depends um we can
Basically install on all of it on an asphalt shingle roof one of the things we’re going to do um is try well first of all here in New Hampshire we need a structural analysis so we’re going to want to get a look at the the structural members size
Spacing of Rafters and then basically we drill a pilot hole once we know where those Rafters are that dies in The rafter so it’s not going to open space actually the the whole dies in The rafter we inject a a a silicone sealant or or kind of caul material lag bolt
Rubber gasket attaches a foot and then the rail goes across uh on standing seam roofs I don’t know last time you guys got a roof priced out they’re not cheap uh they will outlive you though so you know um but those ones we just get a
Little we you know identify what is the spacing between the seams what the profile the size of this seam and we can have these little like almost like a vice that we just take a torque wrench and pinch all over the seams um as far as age is concerned it really
Depends you know the the best time to put a solar array on is when your roof is brand spanking new but nobody likes writing that check unless you absolutely have to so It’s Tricky you know I’m not a roofing expert um I go up on them all
The time but I always and I’m happy to give people you know kind of my general thoughts but typically I say you know have a roofer come out and evaluate it because really what you don’t want is to invest this money in a solar array on
Your roof and then have to get your roof replaced in five years and and pay your contractor to come back disassemble it set it on the ground let your roofer come in do their thing and then put it all back together again so yeah I mean
So I guess on the flip side of that Chris I mean because a couple people have asked in the the questions here as well I mean the other variable being well how old is the roof well how long are these solar panels going to last what is I mean generally the range
You’re seeing or the expectation you’re seeing with some of these systems yeah for roof mounted panels they’re um industry standard is pretty much a 25y year warranty these days yeah um but they’re really designed to produce electricity for 35 40 years put it this way in most projects in my experience
That move forward the system will pay for itself multiple times over in its in its usable life um you know obviously the more advantageous the uh the variables we discussed the more productive the solar array will be typically the the the quicker the return on the investment um but that also depends on
What is our electric consumption like you know sometimes we you know I pull up in a neighborhood of mcmansions and people are using 25,000 kilowatt hours a year and they what what do you mean I can’t you know get 100% offset um so it it’s really um Case by case is what I
Would say that’s incredible uh yeah a lot of variable including uh another one that Martha’s curious about that I’m curious too because on the Mount Washington side of things there’s always this question of uh Martha ask can you safely install solar panels on a residential roof in a high wind area
Martha is saying that um they’re building a a home on the coast of Rhode Island they want to include solar energy the power of the house what’s yeah what’s that wind maximum look like or what do you need to do maybe to to adjust to that I’d have to defer to our
Engineering team on um on on uh you know the top of the Northeast up uh up over your shoulder there Brian I don’t know if we have anything that’s that’s rated for that um but just about everyone else um you know you know we’re a main based company we’re headquartered in South
Portland we’ve got tons of installations on you know on in coastal main right on um you know some pretty rugged coastlines uh you know part of the engineering we review that we do is not only structural but wind and snow loading so all those calculations are being done
Um you know so if there was ever a problem you know sometimes we put in special engineering you know if we really need to bolster something but um you know unless you live at the top of uh the Cog Railway I think we could probably help you out well hey well
We’ll talk after this about helping you break I don’t know I think wind power might be better for uh yeah that’s its own challenges too so there is such thing as too much of a good thing um a couple folks have asked I mean around uh some of the snow
Loading question as well and apologies I’m just gotta Mash together a few different questions here from folks I mean have you seen um well I know you mentioned you know when snow loading is happening perhaps especially on on a roof pitch that maybe is pretty shallow
Or not good to fluff off that snow really quickly have you seen or know of safe and effective ways for clearing that snow or people getting creative and using I don’t know they’re deicing their deicing hoses on their roof or whatever they’re doing anything like that I’ve never heard of anyone pre-treating their
Their solar panels to uh you know to um you know what what is the uh is it one of the the Christmas vacations where they put like Pam on the bottom of the saucer or something yeah yeah I don’t know I don’t know about I don’t know about any of
That but you know so here’s what we’ say we encourage people not to clear their solar panels if they can help it you know um one of the nice things about ground mounts for folks who you know uh maybe have the space is that the front edge of
Kind of that linear racking that I was showing you two and a half three feet off the ground so it’s very easy and safe to go out and clear those snow the the snow off those panels listen it’s your house it’s your panels it’s your money you can do
Whatever you want we’re not in the business of telling people what to do but you know we want people to really be safe and you know for most folks that snow is going to either Slough or melt or a combination of the two on its own
And it’s not worth you know um you know a couple of extra kilowatt hours um you know is not worth you know potentially falling off a ladder in my opinion as someone who who goes on ladders for a living my number one goal every single
Day is to walk back through my own front door under my own power that is that is goal number one so do what you want but I I and full full transparency on our lower roof our garage roof that first floor roof I have a very long extendable pole
With a with a um you know a foam squeegee and I have gone out there and cleared but I I make sure that I’m far enough away that the snow would never Slough on top of me um you know so that’s what I would say do as I say not as I do
Maybe all right well we won’t we won’t tell other employee owners there what you do in your your free time um Chris I mean this is the the million-dollar question obviously for a lot a lot of people who may be curious about solar at their home and all those sorts of things
Sy’s asking you know specifically you know to like your home example if you’re willing to share you know what what did cost look like for you then I know quite a bit has changed even in the the last few years since you’ve installed and I don’t know maybe it’s just helpful to
Give maybe a range on what’s say like the typical um I don’t know array might look like because I’m sure it must vary quite a bit home to home especially based on on demand yeah it does it does it’s and it’s It’s Tricky um first of all my mine
Mine is not a good example because I basically get this you know not only materials but also installation not quite at Cost but pretty darn close we have a pretty one of the perks of working for a um an employee on Solar Company right great um
You know really depends on you know how big the system is you know the larger the system the lower the cost per watt you’re going to see because we have some fixed costs that can be spread out over a larger system size um you know one thing I should say
Is that another big part of my job is to talk to people about you know the the the kind of policy environment we find ourselves in the regulatory environment we find ourselves in you know we have all kinds of incentives now federal tax credits have been around but have varied
Throughout the years so you know my system was installed in 2020 you know a couple months into the pandemic you know solar had been on a really long cost Decline and then because of the you know the the supply chain issues that kind of hit all around the globe and all kinds
Of different Industries you know solar cost bumped up slightly we’ve seen them start to recover again as kind of The Kinks and Supply chains have have evened out and then the inflation reduction act which was passed you know last late summer fall whenever it was signed you
Know we’re really establishing a uh uh or trying to establish a a a solar and battery supply chain here in the United States I would say the trickiest part for us right now and this is residential commercial you know uh grid scale you know the great thing about
Solar and wind and things like that is that the the the fuel is free but the the capital expenditure is up front instead of over time so you you put that money up up front and what’s really been challenging for us as an industry is the high cost of of capital of just
Borrowing so um you I mean you folks all see it um you want to buy a car and and uh get a loan or buy a home you know forget the actual price of the thing thing you know the the borrowing environment it has been challenging so that’s really more the tricky part
Um um you know hopefully that’ll start to to ease a bit but that’s really where where it’s been a little more more challenging but as far as you know I really hesitate to to even guess on on somebody’s you know uh individual situation without knowing more yeah yeah
Well I mean and I guess and the a question here for Mark as well just you know I’m sure it’s changed over time and advantages versus disadvantages of either saying buying out you know buying outright a system or you know Leasing and or you know needing financing to
Support a project like this I’m sure it’s tricky and different for everybody right yeah so I we don’t do leasing um my take on on kind of lease versus buy you know obviously if you’ve got if you’ve got the cash that you can take out of savings or some type of account
And you don’t have to pay any interest great that’s that there’s no better way to do it um the you know the leasing model is really not for us as a business but it’s it’s got its place right and and there can be some shady stuff here but a lot of times
Leases will kind of look like you know you lease the equipment company comes in and installs the the the solar panels on your roof and they B you basically sign a contract where you’re the price of whatever power that they produce from your roof is indexed with the uh with the util with
Your utilities price so you’re going to sign a contract and you’re always going to be 10 or 15% lower than the what the utility uh is charging um however there’s just far far less savings over over time so the nice thing is you may not have to spend a lot
Of money up front um you may not have to apply for financing you know you may not have to qualify for financing or you know have your credit checked or anything like that um so it does have a place no doubt and I would still encourage people who if they think about
Leasing you know um you you still want to work with somebody that’s that’s reputable believe me just anecdotally you know the service department of our company is the fastest growing part of our business we’ve been around for 20 years now we got a lot of systems out in the world um
And we we get call we’re inundated with calls all the time of you know people who have had a system installed and their contractor has up and vanished or the company has gone bankrupt so regardless of what you do I I I can’t stress hard you know enough vet vet your
Contractor um thoroughly so yeah all right could imagine especially if you are making a significant investment um maybe time for just thank you Chris for answering somebody questions that this might be uh close to a record for the amount of questions we’ve gotten actually Brian I’m ready to go Huskies
Don’t play till nine: playing at the Gard against UNC tonight so I tip off at nine so I’m gonna be up late tonight so I can take as many as you want okay well great I love it um couple questions I think around the idea maybe I don’t know maybe
You can talk a little bit this may not be your your wheelhouse around um I for apologies I forgot who asked about this question but around Net metering and I think similarly Kenneth here is asking a question around uh you know if when you are producing more energy than you need
Do all grids or power companies allow you to feed back into the grid and reverse the meter I mean we’re kind I guess talking about Sim similar things net metering could you maybe explain that one just a little bit I know it gets a little a little Technical and
Driven yeah I mean you know broadly speaking net metering is kind of the the frame the financial framework within which we are compensated for over production so again anytime the sun is shining our panels are making power the first responsibility of those electrons in that moment is to go to whatever your
Load demand is if you’re making more than you need at any given moment you’re pushing power out into the grid what you how you’re compensated is is determined on a state byst state and even utility to utility uh basis so it’s different from state to state and even here within the
State you know we’ve got our three major utilities and the New Hampshire Electrical Co-Op NHC and then we have a couple of I think wolfboro has a a municipal uh utility there there may be a couple other Municipal Utilities in town or or in the state um actually the Public Utilities Commission
I think they just closed up a a um a docket you know a couple days ago kind of look they’re going to be making a decision on the future of net metering here in New Hampshire but all the three major utilities all came out in support
Of net metering as it uh is currently constituted here in New Hampshire but I know you know at the poll beginning today we have people from all over New England you know and some folks from even outside of New England so you know I only work in the state of New
Hampshire so I can speak and even in New Hampshire I I’m primarily doing ever Source territory so um basically the way it works is you’re compensated for power that you send out and you’re charged for power that you bring in overnight and you know in times when you’re not
Producing the fine details of what that looks like is really dependent on where you live yeah yeah so just another another piece of the puzzle for sure sure but uh I guess an important one if you know a policy perspective should something change radically but uh
Certainly see that coming up in the news from time to time and like you said depends on where you live I’m wondering um Robert asked a nice question here I don’t know if you can speak uh a little bit more just about you know battery storage and what that kind of looks like
And know you showed your home example and maybe just sort of generally you know what what that’s all about maybe and how you’ve used it and things like that yeah so batteries um again we kind of get into kind of my batteries right now are still kind of
Expensive and at least in New Hampshire for most folks they typically they’re making more and more sense day by day but we’re still not quite at a point where you know maybe I don’t have my crystal ball about five years 10 years I’ll probably never sell a solar project
Without pairing it with batteries because the tech Technologies are really like peanut butter and jelly you know um you know you produce power during the day you store in a battery and you can discharge it at night overnight right or when the grid goes down really that’s the primary function that a battery
Serves right now in New Hampshire at least is if you don’t have a a generator then if the power goes out you have a battery and I should say if you don’t have a battery and you have solar panels and you know your neighbor backs out of of
His driveway and hits the power pole and you lose power you know your solar is not going to produce you know when the grid is down even if it’s sunny and that’s by code that’s to predict we can’t have solar panels back feeding the grid when there’s a grid disruption and you know
It’s a safety thing yeah um but batteries can do all kind you know friends of ours who might be Tuning In from from Vermont you know they have a demand respon response program so what that looks like is is and I don’t know the exact specifics but demand response
Generally is you know August 15th it’s 95 degrees every air conditioner in the state of Vermont is plugged in and cranking away if you were to look at the demand curve you know uh for the grid uh for Vermont as a whole it’s going like a
Rocket ship so what that forces the grid operator to do traditionally is go out and buy really expensive power on the spot Market AB above and beyond those Basel load contracts that they’ve kind of signed and what Vermont has done is incentivized battery installs and people participate in demand response program
So they do what’s called Peak shaving so the grid operator can now remotely discharge all of those batteries all that stored up energy out into the grid to shave the peak off of that demand curve and then as soon as the demand starts to subside those batteries
Recharge so that they’re ready to serve their primary purpose uh you know if the grid goes down yeah in Massachusetts you’ve got you know there I mean there’s all kinds of different kind of regulatory structures smart metering load shifting things like that batteries have an enormous role to play in the
Future um but again that’s a that’s another thing where it’s kind of dep here in New Hampshire we don’t have any battery incentives I believe Massachusetts has a state battery incentive so you know the technolog is going to get cheaper it’s going to get better you’re going to
Get better energy density we’re seeing different chemistries for different applications in 20 years we’re not going to have the same battery chemistries for batteries that sit in your basement and never move as batteries that go in your car you know there’s a lot of really promising iron chemistries iron is I
Think the most plentiful uh element in the Earth’s crust but it’s super heavy so it’s abundant but it’s not exactly what you’d want want underneath your butt when you’re driving down the road but if it’s just going to be in a b in a battery that sits in your basement or
Your garage and never moves then great so there keep an eye on it there I mean we are not far away from batteries just being a no-brainer pairing with solar oh fascinating and of course you mentioned the other those other aspects that you’re working in and um you know heat
Pumps and heat pump hot water heaters and those other technologies that clearly seem to be on a certainly batteries batteries other places in the world the attachment rate which is kind of IND industry G jargon for like solar sold with batteries simultaneously um really really high in places where the
Electric grid may be very unreliable you know just anecdotally the batteries that I’ve sold are usually to people who are you know in really rural communities who if not they’re if they’re not literally the last pole on a dirt road they’re pretty darn close and they’re you know
When they lose power it’s usually for a long time and they’re you know and it’s pretty often so the the value proposition for them is a lot different you know Brian the one other thing I I did want to I didn’t even realize I could see these questions but I there
Were a couple of questions about recycling you know the US really needs recycling policy for solar we can recoup a lot of the materials a huge percent of the the materials in solar panels but right now we don’t really have um good system for that the EU has a really
Robust so kind of cradle to grave solar recycling protocol and so we we can do it same thing with batteries like the ability to actually recycle batteries you know at the end of life and um re-refine those materials and and put them into new batteries so that you know
Um there’s a lot of potential there but we definitely need you know some guidance and you know kind of public private partnership to kind of um push the needle on that I would say if you’re getting a if you’re getting a solar array today by the time it’s um you know
At the end of its um usable life will almost certainly have a good robust uh recycling kind of uh infrastructure uh set up so yeah I appreciate that yeah that that was a question that came up from a couple different individuals and um certainly especially if you’re of
That um you know Eco mindset that’s that’s another piece that I’m sure folks are considering as you mentioned you know one of the many reasons why folks might be interested in uh in solar PV but um Chris you know I’m sorry to leave it leave it here I know for folks who
Joined um this has been fantastic really appreciate you um spending some time with us tonight sharing about your work um if you don’t mind uh maybe for folks who have still more questions that pop up after the program you can always reach me at education mountwashington.org and can pass along
Some questions uh to Chris here uh Chris what’s the best way for folks to get in contact either with with you or with revision is there a preferred way well I’m uh I’m two weeks into um 12 weeks of paternity leave I got a threee three-month-old in the Next Room so uh
You can’t get a hold of me uh for another couple of months um but you know revision energy.com if you want to check us out um we’ve got an incredible team and um one of the many many uh great reasons uh that I love being an employee owner is that we have
12 weeks of paid paternity leave so I get a I get a chance to be um a dad who’s focused basically only on on my son and not answering emails and um but my colleagues will uh will be happy to answer any other questions that you folks have so awesome well Chris I
Really appreciate especially uh doing this on on your leave that that really means a lot to us and congratulations to you and your family that’s that’s exciting stuff Um well hey everyone else who joined this evening thanks thanks so much for joining another science of the mountains program uh if you enjoyed
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Thank you in advance for any of your thoughts there and then finally don’t forget to join us for upcoming science of the mountains program Tuesday January 16th we’ll have McGill University associate professor Renee cyber and the observatory’s executive director Drew Bush will present on their ongoing research looking at how effectively
Social media is being used to keep people safe during extreme weather events and then also on February 20th Fairfield University associate professor Robert nerian will share his research into projecting future Trends and extreme uh precipitation across the Northeastern United States so don’t forget to sign up for those programs
Over at Mount washington.org you can see any of the programs you might have missed uh previously thanks so much for joining everyone tonight and thank you again Chris really appreciate it have a great night thanks everybody appreciate you having me Brian yeah absolutely take care