Solar power

[nat_ster]

I don't understand the need for flexible panels.

In order to maximize solar exposure, the panels need to be flat, facing the sun.

Or are you guys going to contact cement them to the curved bus roof?

Nat

 

[Valkyrie_2]

I like the idea of gluing them down and not poking extra holes in the bus roof to attach panels. I also like the idea of not having a wind trap underneath the panels.

 

[nat_ster]

In the south where the sun is higher in the sky that might work. However up here, the panels need to be set at the optimal angle, and also need to track the sun.

For me the panels will be the single most expensive part of my electrical system. There for they will be mounted on folding mounts, that swivel to track the sun.

Nat

 

[Valkyrie_2]

My plan is to glue two panels on the roof, leaving a central walkway then to build up more panels and batteries as time progresses.

 

[slideforlife]

what about a huge panel running down each side of the bus? After a roof raise, you could more than triple the panel area available than by simply covering the roof. They could be hinged and lift like wings when parked for optimal sunshine. With those two, a panel covering the roof and a huge battery storage pack underneath, maybe they'd even generate enough power to drive?

 

[bubb the real one]

panels

from what I have read,
the individual solar collectors on the panels dont bend well,
not having air circulation underneath the panels will increase their heating and decrease their efficiency,
the bendable clear coat on the panels dont last as long and dont protect the panels as well,

 

[slideforlife]

i was reading about electric vehicle rv and was wondering how much juice it would take to push a bus. then of course, the next question is whether you can capture enough from the sun to keep it going. nevermind the logistics of wind, wear and damage for a minute, would max'ing out the surface space on a bus with panels do it?

 

[nat_ster]

i was reading about electric vehicle rv and was wondering how much juice it would take to push a bus. then of course, the next question is whether you can capture enough from the sun to keep it going. nevermind the logistics of wind, wear and damage for a minute, would max'ing out the surface space on a bus with panels do it?

Sorry not even close.

It would take 500 times what the entire bus coated in panels could make.

Nat

 

[slideforlife]

over on teslamotorclub.com they were talking about 170 Kwh of batteries to get 300 to 400 miles of range for a class c rv. I saw an 25' roof covered with panels getting 3.5 Kwh. Get an 40'er and cover the sides as well and maybe that gets up to 15Kwh. Only 155 more to go before it's there!

EDIT: apparently there's reasons that it may be between 170 - 340 Kwh (probably on the high end) to get 200+ miles. But the solar panels wouldn't have to generate that constantly, right? you go as far as you can, then set up camp and wait to recharge. If you got enough time, with 4 Tesla 85 power packs, it's doable. (just dreaming)

 

[family wagon]

Here's an electric bus that was put into service at the University of Utah campus last year. The article mentions a 50 kW wireless charging system. I don't know how many hours it has to sit on the charger each day at that rate.. but supposing it was just one hour, then if one were going to charge it with solar instead in a place where there are 5 hours of solar insolation to work with, an array would have to produce 10 kW/hr which is about 42 of the common 235 watt panels. I bet this bus spends a lot more than just one hour per day on that charger, though!

 

[Valkyrie_2]

I don't think its impossible. At 170kwh to go 300 miles that's 0.5666kwh\mile so 15kwh would get you 8.5 miles. If, however you park for several days at a time like most rv owners then things look far more possible. At 15kwh\day that's 10 days or so for a full charge. That's eminently possible.

 

[nat_ster]

Do you have a budget for the battery that big?

Nat

 

[Valkyrie_2]

Lol. I don't have space for one that big!

I'm thinking of starting with just plug in while I get everything sorted out then adding batteries then solar panels.

 

[nat_ster]

There are stores here with free electric car charging stations.

If your battery is big enough, you should be able to go for weeks.

Nat

 

[family wagon]

That's sure the truth. In another of the articles I read about that bus at the University, a representative from the Wave charger people mentioned that what makes their charger so great is that it enables shrinking the battery pack from one weighing 10,000 pounds to merely 2,500 pounds. That's a lot of battery!

 

[Valkyrie_2]

That's an interesting idea. I'm not yet comfortable driving my bus so I tend to stay out in the sticks with it. Truth be told, its been parked for the last 2 months.

I'm still working on the interior and also dabbling with recycled cooking oil.

 

[slideforlife]

this guy has two 85 Kwh powerpacks to power his home. the video gives you an idea of how big they are. I wonder how many could fit under a bus?

 

[Dave588]

Generally, PV solar panels are angled at sun. Usually within 10 degrees of your latitude. There is an index of how many solar hours obtained per day. So a 100watt panel, angled correctly, may get 200-300 watts per day. You may be able to build a frame similar to a luggage rack on roof that would protect panels when driving and allow them to tilt at sun when parked. But tilting on one axis would mean parking bus parallel to suns track.

 

[SassyLass]

Solar hot water, solar hydronic heat info-sheets; diesel hot water/heat

From another thread

Diesel hot water and heat:
DickinsonMarine.com - Hot Water Coils

Solar hot water and heat (look through their library and manuals... LOTS of good info here)
Radiant solar heating systems from Radiantec
http://www.radiantsolar.com/pdf/fundamentals.pdf

They have info sheets for all combinations of using solar water heaters with water tanks, heat exchangers, water heaters and hydronic heating. Both in closed/open or direct/indirect combinations.

Long story short- at the least, the solar HW heater boosts the temp of the water in your tank so you need less energy to bring the water up to temp with a water heater. Same concept with hydronic heating. Even if it doesn't fully heat your system, it takes a lot of the load off your electric load for heating.

 

[bearbus]

Just wanted to point out that the major benefit of the flexible solar panels is not necessarily that they flex but that they are light weight and VERY durable. Walking on them is not a problem.