Try R: Code School Course

I'm currently going through the Data Science Specialization on Coursera. You can track my work through the classes here and learn more about the Data Science Specialization here: John Hopkin's University 'Data Science Specialization' track.

I'm taking the courses in order to backfill my understanding of the hows, whys and pitfalls in data analysis. The courses also happen to be in R, which is a language I have literally never used in my day job.

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SketchUp and Solar Power - A Quick Tutorial - Part 2

Pull 4.png

One thing to keep in mind with a solar installation are the local township laws related to solar. 

As a general rule - you want to set yourself a border around the edge of the building where you don't put any solar. Sometimes the roof has a 'lip' that can cause shading -- or the township/building insurace/fire department has rules on how close to the edge you can get.

I'm going to add a 3' border to this demo with one of SketchUp's amazing tools - Offset.

Offset 1.png
Again we can just type in 3' while using the offset tool to get a border

Again we can just type in 3' while using the offset tool to get a border

Now Let's Add the Panels

*** As an added note - At this point you may want to group your entire building into one component or group -- that way nothing that you do to the panels will change the shape of the building ***

You may want to draw your own panels.... but before you do that, you might want to check to see if someone else has already drawn them.. and to scale...

Enter the 3d Warehouse

Warehouse 2.png

Many companies and SketchUp enthusiasts have actually uploaded to-scale renderings of specific models - so if you're designing with a specific panel in mind, you could try searching for that model specifically and you may just get it.

But I'm going to be a bit more general...

Warehouse 3.png

That'll do...

Once you select a model - it'll be dropped at random into your model. 

Panel 1.png

It's hard to tell from this picture - but the panel is currently at a tilt and oriented the wrong direction for the building (remember you're going to want to orient as much to the south as possible - again - this is where a real solar installer can give you the EXACT preferred orientation- but generally you follow the angles of the building as best you can).

rotate 1.png

So we will need to use the rotate tool quite a bit now.

Since 3D drawing can mess with your perspective, I prefer to move to the edge of the building and use the building lines to rotate against. 

Panel 2.png

First we can lock the edge of the panel to the edge of the building to remove the tilt

rotate 2.png
rotate 4.png

Then we can orient the panel so that it'll 'face' south

rotate 5.png
rotate 6.png

Now the border lines come in handy for laying out the solar

rotate 6.png

There are a number of reasons why you don't want to place a solar panel completely flat on a roof. For example, the panels have a small lip around the edges. When it rains, the moisture collects on the panel and then slowly evaporates, leaving behind dust and dirt. This can cut down on efficiency across the panels.

The amount you tilt the panels will depend on the racking you use and the actual location. For the purposes of this rendering, I'll use a 30 degree tilt. 

place 2.png
place 3.png

Just like with placement, you can type in the degree of angle.

We plan to cover the roof though, and it's easier to work with the panels while they're flat - so let's undo the tilt for now

place 5.png

SketchUp has an amazing 'copy' tool - which you should use instead of the Ctrl-C. 

Snag the corner of the panel with the move tool - and then hit 'Option' and you'll duplicate the panel exactly. 

rotate 7.png

In order to replicate a typical racking system, you'll want to put an 1" of space between the panels. 

rotate 8.png

One amazing thing about SketchUp is that it will remember your 1" spacing and automatically jump to that distance when you move future panels.

rotate 9.png
rotate10.png

In the first tutorial I mentioned creating groups or components. As you can tell, the panel model that we imported from the warehouse is actually made of individual lines and planes - but it's been grouped together as one item for ease of use.

We'll do the same thing with this mini-array to populate more panels

populate1.png

We can now copy our little group and start making a longer row

Populate2.png

Now we can group our long array - and just like duplicating panels, we can duplicate the row. 

Spacing between rows of panels is a precise science - but for the purposes of this demo, we can follow our border line and give 6.5' of space.

Here is another cool SketchUp trick:

1. Grab the bottom corner of the array that is touching the border with the Move tool

2. Hit option to create a copy

3. Start moving the duplicated array backwards along the border and then enter 6.5'

4. Now enter 5x -- this will repeat the copy and move backwards 6.5' action five times

Populate 3.png

How. Amazing. Is. That.

Now you'll want to delete that last row... and now that your array is spaced out, you'll want to go through and adjust your array so it's a little better centered on the roof.

As you can see - a lot of the panels are merged into your HVAC units. We're going to want to go through and delete some panels. 

adjust 1.png

First, you'll need to explode the groups of arrays that you made earlier so that you can delete individual panels

SketchUp allows you to 'hide' elements. You can 'hide' the tops on the HVAC units so that you can make sure to delete all panels being hidden within them. We used transparency earlier because we wanted to continue to work on and with the 2D building but in this case, we want the tops of the HVAC units to temporarily not exist and get in our way.

Hiding 1.png

Once you've cleared out all the hidden panels you can batch 'unhide all'.

layout1.png

So now you have the max number of panels that you can physically fit on the roof (taking nothing else under consideration). 

At this point I've forgotten how many I put on there... but there is a quick trick to get a count...

layout2.png

Click on one of the panels and select Entity Info

layout 3.png

And it gives you a count of your panels

So now let's check out the actual layout and get ride of panels that are obviously going to be in shade. 

Before

Before

after.png

Aside from the obvious shading, you also want to be conscious of wire runs, string configuration and the cost of racking. There are a few places where you can set one individual panel by itself, but cost-wise, it's usually not worth it.

So now we have a new count -54 panels

complete.png

So now you have a render that you can present to a client. With your tilt, panel type and count you can give them a rough calculation of how much power you can give them. 

54 panels sounds like a lot - but even so, it probably won't cover the energy usage of the building. That's one of the reasons renderings are so important. You don't want to sell the client more than you can actually realistically build. 

SketchUp is amazing. 

SketchUp and Solar Power - A Quick Tutorial - Part 1

In my past life, I did a lot of SketchUp drawing. For obvious reasons, I'm not able to share the drawings I did for my last company. But I'm currently sitting in on a SketchUp for 3d Printing workshop and I wanted to make a little tutorial walkthrough on a few amazing things about SketchUp and Solar.

Why Render for Solar Power?

Well the obvious reason is so that the client can see what their roof is going to look like. The less obvious reason is Google SketchUp can geolocate -- which means that you can quickly render something close to scale that shows shading though out the day. 

So let's put some solar on my favorite local coffee shop

SketchUp is a free tool - developed by Google and taken over by Trimble - that harnesses the amazing power of google to render 3D drawings. And the version I am using, SketchUp Make is free. 

So first - let's load up SketchUp. The standard template gives you a little guy (it used to be a blond woman about a year ago... curious) and a plain workspace.

Start Up.png

So let's delete the man in khakis and look for my favorite coffee shop. 

How Amazing is Google?

Geolocate2.png

Ah. There she is. Let's import her and try and build up the building.

GeoLocate4.png

We're going to want to trace the 2d building outline

Draw 1.png
Draw 2.png

You can combine the two 'boxes' that make up the building by deleting the separating line

Draw 3.png
As you can tell, the screen shot noise was getting me some stares at the workspace.

As you can tell, the screen shot noise was getting me some stares at the workspace.

The next logical step is to 'raise' the building - so that you now have a 3D object instead of a 2D one.  Resist that temptation though.

If you noticed, the building had a number of HVAC units sitting on the roof. It's unlikely that Rooster and Moon is going to want to remove them for solar -- so we need to add them to our drawing and work around them for solar placement.

So before we go 3D, let's make the background transparent and draw those units in. (don't just delete the background - you'll need it soon)

Transparant 1.png

Before we trace out the hvac units - let's make sure we're on a top down view. 3D rendering can really mess with your brain.

Camera.png

We're going to trace out the boxes. In a real construction situation, we'd want to get actual measurements from someone in the field. Often google images are outdated, so some of the units may have moved or been removed. But for general planning purposes, we can guess-timate. 

Transparant2.png
Transparent3.png

Now that we have our layout - I'm going to 'pull' up the building. I'm going to estimate that the building is, say, 17' tall and that the units are 3'.

Pull Tool.png

In the real world, the actual height of the units is very important. The height of the building is less important, unless you are working with a sloped roof. 

With any tool in SketchUp, you can enter a measurement during or immediately after you've made an action. So when I start the 'pull' up the building, I'll pull it up a little bit and then type in 17', and SketchUp takes care of the rest.

Pull1.png
Oops. I entered 15' instead of 17' 

Oops. I entered 15' instead of 17' 

No problem - I can pull the building up another 2'

No problem - I can pull the building up another 2'

So why does it matter how tall I make the HVAC units?

Because SketchUp can render shading. And shading is the enemy of solar.

Basically, if your panels are shaded during prime solar hours, you will have massive losses of productivity. This is important information for qualifying for solar grants -- but also generally the difference between profiting on your green installation or losing major money.

There are ways to work with shading... such as using microinverters,  which are individual inverters per solar panel.  But microinverters are generally more expensive and almost constantly require repair. There are also hours of the day and times of the year where the solar gain is minimal, and you really don't care if you get shade at 4pm in December.

Making those calls and calculations is why you hire a solar professional. 

But for the purposes of this demo, I can show you how to see the general shading that you're looking at.

Shadows1.png
Shadows2.png

First - turn shadow rendering on - and then you can go ahead and toggle the Shadow Settings to see different times of day and different days of the year

Shadows3.png
Shadows4.png

And Now You Have a Building Primed and Ready for Solar - Check Out Part 2 - Where we actually put solar on the roof!