From 28a806f584f3dd6bf5ed1e706569a07e22d4fa72 Mon Sep 17 00:00:00 2001
From: Aart van Halteren <aart.van.halteren@philips.com>
Date: Mon, 10 Jan 2022 22:27:25 +0100
Subject: [PATCH] Fewer no grid charge months

---
 app/models/cost.rb   | 10 +++++-----
 app/models/entsoe.rb |  6 ++++--
 2 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/app/models/cost.rb b/app/models/cost.rb
index 1a436a7..228bb4d 100644
--- a/app/models/cost.rb
+++ b/app/models/cost.rb
@@ -3,8 +3,8 @@ EASY_ENERGY_TARIFFS = {}
 
 class Cost
  
-      
-  attr_reader :battery, :max_charge_kwh, :entsoe
+  attr_accessor :max_charge_kwh    
+  attr_reader :battery, :entsoe
   
   def initialize(battery_capacity=10.0, max_charge=5.0)
     @entsoe = Entsoe.new
@@ -161,8 +161,8 @@ class Cost
         # charge battery with return_kwh
         return_kwh -= battery.charge(return_kwh)
         
-        if lowest_hour.eql?(formatted_hour) # lowest_hour = "" if small difference between high/low
-          # charge battery during lowest hour
+        if (lowest_hour.eql?(formatted_hour) || entsoe.price_at(formatted_hour) < 0) # lowest_hour = "" if small difference between high/low
+          # charge battery during lowest hour, or when prices are negative
           usage_kwh += battery.charge(max_charge_kwh)
         else
           # if during expensive hours || more than <max_charge_kwh> kwh then discharge_battery
@@ -197,7 +197,7 @@ class Cost
                   oxxio_rate, 
                   oxxio_cost]
       
-      p "%s,%s,%s,%s,%s,%s,%s,%03f,%s,%s,%s,%s,%s" % (one_hour[0..7] + one_hour[8..12].map{|c| format_cost(c)})
+      p "%s,%s,%s,%s,%s,%s,%s,%0.02f,%s,%s,%s,%s,%s" % (one_hour[0..7] + one_hour[8..12].map{|c| format_cost(c)})
       result << one_hour
 
       hour_start = hour_start.advance(:hours => 1)
diff --git a/app/models/entsoe.rb b/app/models/entsoe.rb
index 83f925b..66ed0bb 100644
--- a/app/models/entsoe.rb
+++ b/app/models/entsoe.rb
@@ -10,12 +10,14 @@ class Entsoe
 
   URL = 'https://transparency.entsoe.eu'
   
+  attr_accessor :no_grid_charge_months
   attr_reader :storage_cost
 
   def initialize(api_key = "c2287e07-0c26-4950-b430-22b7f75a8f2e")
     @api_key = api_key
     @kwh_prices = {}  
     @storage_cost = 0.05 # how much does it cost to store 1 kwh in battery
+    @no_grid_charge_months = [5,6,7] # months where we assume there is enough surplus from sun power
   end
   
   def price_at(formatted_hour)
@@ -42,8 +44,8 @@ class Entsoe
     sorted_prices = prices_at(date).to_a.sort_by(&:last) # sort according to price 
     highest_hour = sorted_prices.last[0] 
     
-    # From Apr-Oct: do not charge; every hour that has cost > 0 is a high_hour
-    if [4,5,6,7,8,9,10].include?(date.month)
+    # Some months: do not charge; every hour that has cost > 0 is a high_hour
+    if @no_grid_charge_months.include?(date.month)
       lowest_hour = "" # effectively no charging from grid
       high_hours = sorted_prices.select{|p| p[1] > 0}.to_h.keys
     else